wip

Co-authored-by: J. Nick Koston <nick@koston.org>

esphome/analyze_memory/__init__.py

@@ -43,6 +43,7 @@ _READELF_SECTION_PATTERN = re.compile(
 # Component category prefixes
 _COMPONENT_PREFIX_ESPHOME = "[esphome]"
 _COMPONENT_PREFIX_EXTERNAL = "[external]"
+_COMPONENT_PREFIX_LIB = "[lib]"
 _COMPONENT_CORE = f"{_COMPONENT_PREFIX_ESPHOME}core"
 _COMPONENT_API = f"{_COMPONENT_PREFIX_ESPHOME}api"
 
@@ -56,6 +57,16 @@ SymbolInfoType = tuple[str, int, str]
 # RAM sections - symbols in these sections consume RAM
 RAM_SECTIONS = frozenset([".data", ".bss"])
 
+# nm symbol types for global/weak defined symbols (used for library symbol mapping)
+# Only global (uppercase) and weak symbols are safe to use - local symbols (lowercase)
+# can have name collisions across compilation units
+_NM_DEFINED_GLOBAL_TYPES = frozenset({"T", "D", "B", "R", "W", "V"})
+
+# Pattern matching compiler-generated local names that can collide across compilation
+# units (e.g., packet$19, buf$20, flag$5261). These are unsafe for name-based lookup.
+# Does NOT match mangled C++ names with optimization suffixes (e.g., func$isra$0).
+_COMPILER_LOCAL_PATTERN = re.compile(r"^[a-zA-Z_]\w*\$\d+$")
+
 
 @dataclass
 class MemorySection:
@@ -179,11 +190,19 @@ class MemoryAnalyzer:
         self._sdk_symbols: list[SDKSymbol] = []
         # CSWTCH symbols: list of (name, size, source_file, component)
         self._cswtch_symbols: list[tuple[str, int, str, str]] = []
+        # Library symbol mapping: symbol_name -> library_name
+        self._lib_symbol_map: dict[str, str] = {}
+        # Library dir to name mapping: "lib641" -> "espsoftwareserial",
+        # "espressif__mdns" -> "mdns"
+        self._lib_hash_to_name: dict[str, str] = {}
+        # Heuristic category to library redirect: "mdns_lib" -> "[lib]mdns"
+        self._heuristic_to_lib: dict[str, str] = {}
 
     def analyze(self) -> dict[str, ComponentMemory]:
         """Analyze the ELF file and return component memory usage."""
         self._parse_sections()
         self._parse_symbols()
+        self._scan_libraries()
         self._categorize_symbols()
         self._analyze_cswtch_symbols()
         self._analyze_sdk_libraries()
@@ -328,15 +347,19 @@ class MemoryAnalyzer:
             # If no component match found, it's core
             return _COMPONENT_CORE
 
+        # Check library symbol map (more accurate than heuristic patterns)
+        if lib_name := self._lib_symbol_map.get(symbol_name):
+            return f"{_COMPONENT_PREFIX_LIB}{lib_name}"
+
         # Check against symbol patterns
         for component, patterns in SYMBOL_PATTERNS.items():
             if any(pattern in symbol_name for pattern in patterns):
-                return component
+                return self._heuristic_to_lib.get(component, component)
 
         # Check against demangled patterns
         for component, patterns in DEMANGLED_PATTERNS.items():
             if any(pattern in demangled for pattern in patterns):
-                return component
+                return self._heuristic_to_lib.get(component, component)
 
         # Special cases that need more complex logic
 
@@ -384,6 +407,327 @@ class MemoryAnalyzer:
 
         return "Other Core"
 
+    def _discover_pio_libraries(
+        self,
+        libraries: dict[str, list[Path]],
+        hash_to_name: dict[str, str],
+    ) -> None:
+        """Discover PlatformIO third-party libraries from the build directory.
+
+        Scans ``lib<hex>/`` directories under ``.pioenvs/<env>/`` to find
+        library names and their ``.a`` archive or ``.o`` file paths.
+
+        Args:
+            libraries: Dict to populate with library name -> file path list mappings.
+                Prefers ``.a`` archives when available, falls back to ``.o`` files
+                (e.g., pioarduino ESP32 Arduino builds only produce ``.o`` files).
+            hash_to_name: Dict to populate with dir name -> library name mappings
+                for CSWTCH attribution (e.g., ``lib641`` -> ``espsoftwareserial``).
+        """
+        build_dir = self.elf_path.parent
+
+        for entry in build_dir.iterdir():
+            if not entry.is_dir() or not entry.name.startswith("lib"):
+                continue
+            # Validate that the suffix after "lib" is a hex hash
+            hex_part = entry.name[3:]
+            if not hex_part:
+                continue
+            try:
+                int(hex_part, 16)
+            except ValueError:
+                continue
+
+            # Each lib<hex>/ directory contains a subdirectory named after the library
+            for lib_subdir in entry.iterdir():
+                if not lib_subdir.is_dir():
+                    continue
+                lib_name = lib_subdir.name.lower()
+
+                # Prefer .a archive (lib<LibraryName>.a), fall back to .o files
+                # e.g., lib72a/ESPAsyncTCP/... has lib72a/libESPAsyncTCP.a
+                archive = entry / f"lib{lib_subdir.name}.a"
+                if archive.exists():
+                    file_paths = [archive]
+                elif archives := list(entry.glob("*.a")):
+                    # Case-insensitive fallback
+                    file_paths = [archives[0]]
+                else:
+                    # No .a archive (e.g., pioarduino CMake builds) - use .o files
+                    file_paths = sorted(lib_subdir.rglob("*.o"))
+
+                if file_paths:
+                    libraries[lib_name] = file_paths
+                    hash_to_name[entry.name] = lib_name
+                    _LOGGER.debug(
+                        "Discovered PlatformIO library: %s -> %s",
+                        lib_subdir.name,
+                        file_paths[0],
+                    )
+
+    def _discover_idf_managed_components(
+        self,
+        libraries: dict[str, list[Path]],
+        hash_to_name: dict[str, str],
+    ) -> None:
+        """Discover ESP-IDF managed component libraries from the build directory.
+
+        ESP-IDF managed components (from the IDF component registry) use a
+        ``<vendor>__<name>`` naming convention. Source files live under
+        ``managed_components/<vendor>__<name>/`` and the compiled archives are at
+        ``esp-idf/<vendor>__<name>/lib<vendor>__<name>.a``.
+
+        Args:
+            libraries: Dict to populate with library name -> file path list mappings.
+            hash_to_name: Dict to populate with dir name -> library name mappings
+                for CSWTCH attribution (e.g., ``espressif__mdns`` -> ``mdns``).
+        """
+        build_dir = self.elf_path.parent
+
+        managed_dir = build_dir / "managed_components"
+        if not managed_dir.is_dir():
+            return
+
+        espidf_dir = build_dir / "esp-idf"
+
+        for entry in managed_dir.iterdir():
+            if not entry.is_dir() or "__" not in entry.name:
+                continue
+
+            # Extract the short name: espressif__mdns -> mdns
+            full_name = entry.name  # e.g., espressif__mdns
+            short_name = full_name.split("__", 1)[1].lower()
+
+            # Find the .a archive under esp-idf/<vendor>__<name>/
+            archive = espidf_dir / full_name / f"lib{full_name}.a"
+            if archive.exists():
+                libraries[short_name] = [archive]
+                hash_to_name[full_name] = short_name
+                _LOGGER.debug(
+                    "Discovered IDF managed component: %s -> %s",
+                    short_name,
+                    archive,
+                )
+
+    def _build_library_symbol_map(
+        self, libraries: dict[str, list[Path]]
+    ) -> dict[str, str]:
+        """Build a symbol-to-library mapping from library archives or object files.
+
+        Runs ``nm --defined-only`` on each ``.a`` or ``.o`` file to collect
+        global and weak defined symbols.
+
+        Args:
+            libraries: Dictionary mapping library name to list of file paths
+                (``.a`` archives or ``.o`` object files).
+
+        Returns:
+            Dictionary mapping symbol name to library name.
+        """
+        symbol_map: dict[str, str] = {}
+
+        if not self.nm_path:
+            return symbol_map
+
+        for lib_name, file_paths in libraries.items():
+            result = run_tool(
+                [self.nm_path, "--defined-only", *(str(p) for p in file_paths)],
+                timeout=10,
+            )
+            if result is None or result.returncode != 0:
+                continue
+
+            for line in result.stdout.splitlines():
+                parts = line.split()
+                if len(parts) < 3:
+                    continue
+
+                sym_type = parts[-2]
+                sym_name = parts[-1]
+
+                # Include global defined symbols (uppercase) and weak symbols (W/V)
+                if sym_type in _NM_DEFINED_GLOBAL_TYPES:
+                    symbol_map[sym_name] = lib_name
+
+        return symbol_map
+
+    @staticmethod
+    def _build_heuristic_to_lib_mapping(
+        library_names: set[str],
+    ) -> dict[str, str]:
+        """Build mapping from heuristic pattern categories to discovered libraries.
+
+        Heuristic categories like ``mdns_lib``, ``web_server_lib``, ``async_tcp``
+        exist as approximations for library attribution.  When we discover the
+        actual library, symbols matching those heuristics should be redirected
+        to the ``[lib]`` category instead.
+
+        The mapping is built by checking if the normalized category name
+        (stripped of ``_lib`` suffix and underscores) appears as a substring
+        of any discovered library name.
+
+        Examples::
+
+            mdns_lib -> mdns -> in "mdns" or "esp8266mdns" -> [lib]mdns
+            web_server_lib -> webserver -> in "espasyncwebserver" -> [lib]espasyncwebserver
+            async_tcp -> asynctcp -> in "espasynctcp" -> [lib]espasynctcp
+
+        Args:
+            library_names: Set of discovered library names (lowercase).
+
+        Returns:
+            Dictionary mapping heuristic category to ``[lib]<name>`` string.
+        """
+        mapping: dict[str, str] = {}
+        all_categories = set(SYMBOL_PATTERNS) | set(DEMANGLED_PATTERNS)
+
+        for category in all_categories:
+            base = category.removesuffix("_lib").replace("_", "")
+            # Collect all libraries whose name contains the base string
+            candidates = [lib_name for lib_name in library_names if base in lib_name]
+            if not candidates:
+                continue
+
+            # Choose a deterministic "best" match:
+            #   1. Prefer exact name matches over substring matches.
+            #   2. Among non-exact matches, prefer the shortest library name.
+            #   3. Break remaining ties lexicographically.
+            best_lib = min(
+                candidates,
+                key=lambda lib_name, _base=base: (
+                    lib_name != _base,
+                    len(lib_name),
+                    lib_name,
+                ),
+            )
+            mapping[category] = f"{_COMPONENT_PREFIX_LIB}{best_lib}"
+
+        if mapping:
+            _LOGGER.debug(
+                "Heuristic-to-library redirects: %s",
+                ", ".join(f"{k} -> {v}" for k, v in sorted(mapping.items())),
+            )
+
+        return mapping
+
+    def _parse_map_file(self) -> dict[str, str] | None:
+        """Parse linker map file to build authoritative symbol-to-library mapping.
+
+        The linker map file contains the definitive source attribution for every
+        symbol, including local/static ones that ``nm`` cannot safely export.
+
+        Map file format (GNU ld)::
+
+            .text._mdns_service_task
+                        0x400e9fdc      0x65c  .pioenvs/env/esp-idf/espressif__mdns/libespressif__mdns.a(mdns.c.o)
+
+        Each section entry has a ``.section.symbol_name`` line followed by an
+        indented line with address, size, and source path.
+
+        Returns:
+            Symbol-to-library dict, or ``None`` if no usable map file exists.
+        """
+        map_path = self.elf_path.with_suffix(".map")
+        if not map_path.exists() or map_path.stat().st_size < 10000:
+            return None
+
+        _LOGGER.info("Parsing linker map file: %s", map_path.name)
+
+        try:
+            map_text = map_path.read_text(encoding="utf-8", errors="replace")
+        except OSError as err:
+            _LOGGER.warning("Failed to read map file: %s", err)
+            return None
+
+        symbol_map: dict[str, str] = {}
+        current_symbol: str | None = None
+        section_prefixes = (".text.", ".rodata.", ".data.", ".bss.", ".literal.")
+
+        for line in map_text.splitlines():
+            # Match section.symbol line: " .text.symbol_name"
+            # Single space indent, starts with dot
+            if len(line) > 2 and line[0] == " " and line[1] == ".":
+                stripped = line.strip()
+                for prefix in section_prefixes:
+                    if stripped.startswith(prefix):
+                        current_symbol = stripped[len(prefix) :]
+                        break
+                else:
+                    current_symbol = None
+                continue
+
+            # Match source attribution line: "        0xADDR  0xSIZE  source_path"
+            if current_symbol is None:
+                continue
+
+            fields = line.split()
+            # Skip compiler-generated local names (e.g., packet$19, buf$20)
+            # that can collide across compilation units
+            if (
+                len(fields) >= 3
+                and fields[0].startswith("0x")
+                and fields[1].startswith("0x")
+                and not _COMPILER_LOCAL_PATTERN.match(current_symbol)
+            ):
+                source_path = fields[2]
+                # Check if source path contains a known library directory
+                for dir_key, lib_name in self._lib_hash_to_name.items():
+                    if dir_key in source_path:
+                        symbol_map[current_symbol] = lib_name
+                        break
+
+            current_symbol = None
+
+        return symbol_map or None
+
+    def _scan_libraries(self) -> None:
+        """Discover third-party libraries and build symbol mapping.
+
+        Scans both PlatformIO ``lib<hex>/`` directories (Arduino builds) and
+        ESP-IDF ``managed_components/`` (IDF builds) to find library archives.
+
+        Uses the linker map file for authoritative symbol attribution when
+        available, falling back to ``nm`` scanning with heuristic redirects.
+        """
+        libraries: dict[str, list[Path]] = {}
+        self._discover_pio_libraries(libraries, self._lib_hash_to_name)
+        self._discover_idf_managed_components(libraries, self._lib_hash_to_name)
+
+        if not libraries:
+            _LOGGER.debug("No third-party libraries found")
+            return
+
+        _LOGGER.info(
+            "Scanning %d libraries: %s",
+            len(libraries),
+            ", ".join(sorted(libraries)),
+        )
+
+        # Heuristic redirect catches local symbols (e.g., mdns_task_buffer$14)
+        # that can't be safely added to the symbol map due to name collisions
+        self._heuristic_to_lib = self._build_heuristic_to_lib_mapping(
+            set(libraries.keys())
+        )
+
+        # Try linker map file first (authoritative, includes local symbols)
+        map_symbols = self._parse_map_file()
+        if map_symbols is not None:
+            self._lib_symbol_map = map_symbols
+            _LOGGER.info(
+                "Built library symbol map from linker map: %d symbols",
+                len(self._lib_symbol_map),
+            )
+            return
+
+        # Fall back to nm scanning (global symbols only)
+        self._lib_symbol_map = self._build_library_symbol_map(libraries)
+
+        _LOGGER.info(
+            "Built library symbol map from nm: %d symbols from %d libraries",
+            len(self._lib_symbol_map),
+            len(libraries),
+        )
+
     def _find_object_files_dir(self) -> Path | None:
         """Find the directory containing object files for this build.
 
@@ -397,47 +741,38 @@ class MemoryAnalyzer:
             return pioenvs_dir
         return None
 
-    def _scan_cswtch_in_objects(
-        self, obj_dir: Path
-    ) -> dict[str, list[tuple[str, int]]]:
-        """Scan object files for CSWTCH symbols using a single nm invocation.
+    @staticmethod
+    def _parse_nm_cswtch_output(
+        output: str,
+        base_dir: Path | None,
+        cswtch_map: dict[str, list[tuple[str, int]]],
+    ) -> None:
+        """Parse nm output for CSWTCH symbols and add to cswtch_map.
 
-        Uses ``nm --print-file-name -S`` on all ``.o`` files at once.
-        Output format: ``/path/to/file.o:address size type name``
+        Handles both ``.o`` files and ``.a`` archives.
+
+        nm output formats::
+
+            .o files:  /path/file.o:hex_addr hex_size type name
+            .a files:  /path/lib.a:member.o:hex_addr hex_size type name
+
+        For ``.o`` files, paths are made relative to *base_dir* when possible.
+        For ``.a`` archives (detected by ``:`` in the file portion), paths are
+        formatted as ``archive_stem/member.o`` (e.g. ``liblwip2-536-feat/lwip-esp.o``).
 
         Args:
-            obj_dir: Directory containing object files (.pioenvs/<env>/)
-
-        Returns:
-            Dict mapping "CSWTCH$NNN:size" to list of (source_file, size) tuples.
+            output: Raw stdout from ``nm --print-file-name -S``.
+            base_dir: Base directory for computing relative paths of ``.o`` files.
+                      Pass ``None`` when scanning archives outside the build tree.
+            cswtch_map: Dict to populate, mapping ``"CSWTCH$N:size"`` to source list.
         """
-        cswtch_map: dict[str, list[tuple[str, int]]] = defaultdict(list)
-
-        if not self.nm_path:
-            return cswtch_map
-
-        # Find all .o files recursively, sorted for deterministic output
-        obj_files = sorted(obj_dir.rglob("*.o"))
-        if not obj_files:
-            return cswtch_map
-
-        _LOGGER.debug("Scanning %d object files for CSWTCH symbols", len(obj_files))
-
-        # Single nm call with --print-file-name for all object files
-        result = run_tool(
-            [self.nm_path, "--print-file-name", "-S"] + [str(f) for f in obj_files],
-            timeout=30,
-        )
-        if result is None or result.returncode != 0:
-            return cswtch_map
-
-        for line in result.stdout.splitlines():
+        for line in output.splitlines():
             if "CSWTCH$" not in line:
                 continue
 
             # Split on last ":" that precedes a hex address.
-            # nm --print-file-name format: filepath:hex_addr hex_size type name
-            # We split from the right: find the last colon followed by hex digits.
+            # For .o:  "filepath.o" : "hex_addr hex_size type name"
+            # For .a:  "filepath.a:member.o" : "hex_addr hex_size type name"
             parts_after_colon = line.rsplit(":", 1)
             if len(parts_after_colon) != 2:
                 continue
@@ -457,16 +792,89 @@ class MemoryAnalyzer:
             except ValueError:
                 continue
 
-            # Get relative path from obj_dir for readability
-            try:
-                rel_path = str(Path(file_path).relative_to(obj_dir))
-            except ValueError:
+            # Determine readable source path
+            # Use ".a:" to detect archive format (not bare ":" which matches
+            # Windows drive letters like "C:\...\file.o").
+            if ".a:" in file_path:
+                # Archive format: "archive.a:member.o" → "archive_stem/member.o"
+                archive_part, member = file_path.rsplit(":", 1)
+                archive_name = Path(archive_part).stem
+                rel_path = f"{archive_name}/{member}"
+            elif base_dir is not None:
+                try:
+                    rel_path = str(Path(file_path).relative_to(base_dir))
+                except ValueError:
+                    rel_path = file_path
+            else:
                 rel_path = file_path
 
             key = f"{sym_name}:{size}"
             cswtch_map[key].append((rel_path, size))
 
-        return cswtch_map
+    def _run_nm_cswtch_scan(
+        self,
+        files: list[Path],
+        base_dir: Path | None,
+        cswtch_map: dict[str, list[tuple[str, int]]],
+    ) -> None:
+        """Run nm on *files* and add any CSWTCH symbols to *cswtch_map*.
+
+        Args:
+            files: Object (``.o``) or archive (``.a``) files to scan.
+            base_dir: Base directory for relative path computation (see
+                      :meth:`_parse_nm_cswtch_output`).
+            cswtch_map: Dict to populate with results.
+        """
+        if not self.nm_path or not files:
+            return
+
+        _LOGGER.debug("Scanning %d files for CSWTCH symbols", len(files))
+
+        result = run_tool(
+            [self.nm_path, "--print-file-name", "-S"] + [str(f) for f in files],
+            timeout=30,
+        )
+        if result is None or result.returncode != 0:
+            _LOGGER.debug(
+                "nm failed or timed out scanning %d files for CSWTCH symbols",
+                len(files),
+            )
+            return
+
+        self._parse_nm_cswtch_output(result.stdout, base_dir, cswtch_map)
+
+    def _scan_cswtch_in_sdk_archives(
+        self, cswtch_map: dict[str, list[tuple[str, int]]]
+    ) -> None:
+        """Scan SDK library archives (.a) for CSWTCH symbols.
+
+        Prebuilt SDK libraries (e.g. lwip, bearssl) are not compiled from source,
+        so their CSWTCH symbols only exist inside ``.a`` archives.  Results are
+        merged into *cswtch_map* for keys not already found in ``.o`` files.
+
+        The same source file (e.g. ``lwip-esp.o``) often appears in multiple
+        library variants (``liblwip2-536.a``, ``liblwip2-1460-feat.a``, etc.),
+        so results are deduplicated by member name.
+        """
+        sdk_dirs = self._find_sdk_library_dirs()
+        if not sdk_dirs:
+            return
+
+        sdk_archives = sorted(a for sdk_dir in sdk_dirs for a in sdk_dir.glob("*.a"))
+
+        sdk_map: dict[str, list[tuple[str, int]]] = defaultdict(list)
+        self._run_nm_cswtch_scan(sdk_archives, None, sdk_map)
+
+        # Merge SDK results, deduplicating by member name.
+        for key, sources in sdk_map.items():
+            if key in cswtch_map:
+                continue
+            seen: dict[str, tuple[str, int]] = {}
+            for path, sz in sources:
+                member = Path(path).name
+                if member not in seen:
+                    seen[member] = (path, sz)
+            cswtch_map[key] = list(seen.values())
 
     def _source_file_to_component(self, source_file: str) -> str:
         """Map a source object file path to its component name.
@@ -495,9 +903,21 @@ class MemoryAnalyzer:
         if "esphome" in parts and "components" not in parts:
             return _COMPONENT_CORE
 
-        # Framework/library files - return the first path component
-        # e.g., lib65b/ESPAsyncTCP/... -> lib65b
-        #        FrameworkArduino/... -> FrameworkArduino
+        # Framework/library files - check for PlatformIO library hash dirs
+        # e.g., lib65b/ESPAsyncTCP/... -> [lib]espasynctcp
+        if parts and parts[0] in self._lib_hash_to_name:
+            return f"{_COMPONENT_PREFIX_LIB}{self._lib_hash_to_name[parts[0]]}"
+
+        # ESP-IDF managed components: managed_components/espressif__mdns/... -> [lib]mdns
+        if (
+            len(parts) >= 2
+            and parts[0] == "managed_components"
+            and parts[1] in self._lib_hash_to_name
+        ):
+            return f"{_COMPONENT_PREFIX_LIB}{self._lib_hash_to_name[parts[1]]}"
+
+        # Other framework/library files - return the first path component
+        # e.g., FrameworkArduino/... -> FrameworkArduino
         return parts[0] if parts else source_file
 
     def _analyze_cswtch_symbols(self) -> None:
@@ -505,17 +925,25 @@ class MemoryAnalyzer:
 
         CSWTCH symbols are compiler-generated lookup tables for switch statements.
         They are local symbols, so the same name can appear in different object files.
-        This method scans .o files to attribute them to their source components.
+        This method scans .o files and SDK archives to attribute them to their
+        source components.
         """
         obj_dir = self._find_object_files_dir()
         if obj_dir is None:
             _LOGGER.debug("No object files directory found, skipping CSWTCH analysis")
             return
 
-        # Scan object files for CSWTCH symbols
-        cswtch_map = self._scan_cswtch_in_objects(obj_dir)
+        # Scan build-dir object files for CSWTCH symbols
+        cswtch_map: dict[str, list[tuple[str, int]]] = defaultdict(list)
+        self._run_nm_cswtch_scan(sorted(obj_dir.rglob("*.o")), obj_dir, cswtch_map)
+
+        # Also scan SDK library archives (.a) for CSWTCH symbols.
+        # Prebuilt SDK libraries (e.g. lwip, bearssl) are not compiled from source
+        # so their symbols only exist inside .a archives, not as loose .o files.
+        self._scan_cswtch_in_sdk_archives(cswtch_map)
+
         if not cswtch_map:
-            _LOGGER.debug("No CSWTCH symbols found in object files")
+            _LOGGER.debug("No CSWTCH symbols found in object files or SDK archives")
             return
 
         # Collect CSWTCH symbols from the ELF (already parsed in sections)

esphome/analyze_memory/cli.py

@@ -14,6 +14,7 @@ from . import (
     _COMPONENT_CORE,
     _COMPONENT_PREFIX_ESPHOME,
     _COMPONENT_PREFIX_EXTERNAL,
+    _COMPONENT_PREFIX_LIB,
     RAM_SECTIONS,
     MemoryAnalyzer,
 )
@@ -407,6 +408,11 @@ class MemoryAnalyzerCLI(MemoryAnalyzer):
             for name, mem in components
             if name.startswith(_COMPONENT_PREFIX_EXTERNAL)
         ]
+        library_components = [
+            (name, mem)
+            for name, mem in components
+            if name.startswith(_COMPONENT_PREFIX_LIB)
+        ]
 
         top_esphome_components = sorted(
             esphome_components, key=lambda x: x[1].flash_total, reverse=True
@@ -417,6 +423,11 @@ class MemoryAnalyzerCLI(MemoryAnalyzer):
             external_components, key=lambda x: x[1].flash_total, reverse=True
         )
 
+        # Include all library components
+        top_library_components = sorted(
+            library_components, key=lambda x: x[1].flash_total, reverse=True
+        )
+
         # Check if API component exists and ensure it's included
         api_component = None
         for name, mem in components:
@@ -435,10 +446,11 @@ class MemoryAnalyzerCLI(MemoryAnalyzer):
             if name in system_components_to_include
         ]
 
-        # Combine all components to analyze: top ESPHome + all external + API if not already included + system components
+        # Combine all components to analyze: top ESPHome + all external + libraries + API if not already included + system components
         components_to_analyze = (
             list(top_esphome_components)
             + list(top_external_components)
+            + list(top_library_components)
             + system_components
         )
         if api_component and api_component not in components_to_analyze:

esphome/components/epaper_spi/colorconv.h

@@ -0,0 +1,67 @@
+#pragma once
+
+#include <cstdint>
+#include <algorithm>
+#include "esphome/core/color.h"
+
+/* Utility for converting internal \a Color RGB representation to supported IC hardware color keys
+ *
+ * Focus in driver layer is on efficiency.
+ * For optimum output quality on RGB inputs consider offline color keying/dithering.
+ * Also see e.g. Image component.
+ */
+
+namespace esphome::epaper_spi {
+
+/** Delta for when to regard as gray */
+static constexpr uint8_t COLORCONV_GRAY_THRESHOLD = 50;
+
+/** Map RGB color to discrete BWYR hex 4 color key
+ *
+ * @tparam NATIVE_COLOR  Type of native hardware color values
+ * @param color     RGB color to convert from
+ * @param hw_black  Native value for black
+ * @param hw_white  Native value for white
+ * @param hw_yellow Native value for yellow
+ * @param hw_red    Native value for red
+ * @return          Converted native hardware color value
+ * @internal Constexpr. Does not depend on side effects ("pure").
+ */
+template<typename NATIVE_COLOR>
+constexpr NATIVE_COLOR color_to_bwyr(Color color, NATIVE_COLOR hw_black, NATIVE_COLOR hw_white, NATIVE_COLOR hw_yellow,
+                                     NATIVE_COLOR hw_red) {
+  // --- Step 1: Check for Grayscale (Black or White) ---
+  // We define "grayscale" as a color where the min and max components
+  // are close to each other.
+
+  const auto [min_rgb, max_rgb] = std::minmax({color.r, color.g, color.b});
+
+  if ((max_rgb - min_rgb) < COLORCONV_GRAY_THRESHOLD) {
+    // It's a shade of gray. Map to BLACK or WHITE.
+    // We split the luminance at the halfway point (382 = (255*3)/2)
+    if ((static_cast<int>(color.r) + color.g + color.b) > 382) {
+      return hw_white;
+    }
+    return hw_black;
+  }
+
+  // --- Step 2: Check for Primary/Secondary Colors ---
+  // If it's not gray, it's a color. We check which components are
+  // "on" (over 128) vs "off". This divides the RGB cube into 8 corners.
+  const bool r_on = (color.r > 128);
+  const bool g_on = (color.g > 128);
+  const bool b_on = (color.b > 128);
+
+  if (r_on) {
+    if (!b_on) {
+      return g_on ? hw_yellow : hw_red;
+    }
+
+    // At least red+blue high (but not gray) -> White
+    return hw_white;
+  } else {
+    return (b_on && g_on) ? hw_white : hw_black;
+  }
+}
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/epaper_spi_jd79660.cpp

@@ -0,0 +1,227 @@
+#include "epaper_spi_jd79660.h"
+#include "colorconv.h"
+
+#include "esphome/core/log.h"
+
+namespace esphome::epaper_spi {
+static constexpr const char *const TAG = "epaper_spi.jd79660";
+
+/** Pixel color as 2bpp. Must match IC LUT values. */
+enum JD79660Color : uint8_t {
+  BLACK = 0b00,
+  WHITE = 0b01,
+  YELLOW = 0b10,
+  RED = 0b11,
+};
+
+/** Map RGB color to JD79660 BWYR hex color keys */
+static JD79660Color HOT color_to_hex(Color color) {
+  return color_to_bwyr(color, JD79660Color::BLACK, JD79660Color::WHITE, JD79660Color::YELLOW, JD79660Color::RED);
+}
+
+void EPaperJD79660::fill(Color color) {
+  // If clipping is active, fall back to base implementation
+  if (this->get_clipping().is_set()) {
+    EPaperBase::fill(color);
+    return;
+  }
+
+  const auto pixel_color = color_to_hex(color);
+
+  // We store 4 pixels per byte
+  this->buffer_.fill(pixel_color | (pixel_color << 2) | (pixel_color << 4) | (pixel_color << 6));
+}
+
+void HOT EPaperJD79660::draw_pixel_at(int x, int y, Color color) {
+  if (!this->rotate_coordinates_(x, y))
+    return;
+  const auto pixel_bits = color_to_hex(color);
+  const uint32_t pixel_position = x + y * this->get_width_internal();
+  // We store 4 pixels per byte at LSB offsets 6, 4, 2, 0
+  const uint32_t byte_position = pixel_position / 4;
+  const uint32_t bit_offset = 6 - ((pixel_position % 4) * 2);
+  const auto original = this->buffer_[byte_position];
+
+  this->buffer_[byte_position] = (original & (~(0b11 << bit_offset))) |  // mask old 2bpp
+                                 (pixel_bits << bit_offset);             // add new 2bpp
+}
+
+bool EPaperJD79660::reset() {
+  // On entry state RESET set step, next state will be RESET_END
+  if (this->state_ == EPaperState::RESET) {
+    this->step_ = FSMState::RESET_STEP0_H;
+  }
+
+  switch (this->step_) {
+    case FSMState::RESET_STEP0_H:
+      // Step #0: Reset H for some settle time.
+
+      ESP_LOGVV(TAG, "reset #0");
+      this->reset_pin_->digital_write(true);
+
+      this->reset_duration_ = SLEEP_MS_RESET0;
+      this->step_ = FSMState::RESET_STEP1_L;
+      return false;  // another loop: step #1 below
+
+    case FSMState::RESET_STEP1_L:
+      // Step #1: Reset L pulse for slightly >1.5ms.
+      // This is actual reset trigger.
+
+      ESP_LOGVV(TAG, "reset #1");
+
+      // As commented on SLEEP_MS_RESET1: Reset pulse must happen within time window.
+      // So do not use FSM loop, and avoid other calls/logs during pulse below.
+      this->reset_pin_->digital_write(false);
+      delay(SLEEP_MS_RESET1);
+      this->reset_pin_->digital_write(true);
+
+      this->reset_duration_ = SLEEP_MS_RESET2;
+      this->step_ = FSMState::RESET_STEP2_IDLECHECK;
+      return false;  // another loop: step #2 below
+
+    case FSMState::RESET_STEP2_IDLECHECK:
+      // Step #2: Basically finished. Check sanity, and move FSM to INITIALISE state
+      ESP_LOGVV(TAG, "reset #2");
+
+      if (!this->is_idle_()) {
+        // Expectation: Idle after reset + settle time.
+        // Improperly connected/unexpected hardware?
+        // Error path reproducable e.g. with disconnected VDD/... pins
+        // (optimally while busy_pin configured with local pulldown).
+        // -> Mark failed to avoid followup problems.
+        this->mark_failed(LOG_STR("Busy after reset"));
+      }
+      break;  // End state loop below
+
+    default:
+      // Unexpected step = bug?
+      this->mark_failed();
+  }
+
+  this->step_ = FSMState::INIT_STEP0_REGULARINIT;  // reset for initialize state
+  return true;
+}
+
+bool EPaperJD79660::initialise(bool partial) {
+  switch (this->step_) {
+    case FSMState::INIT_STEP0_REGULARINIT:
+      // Step #0: Regular init sequence
+      ESP_LOGVV(TAG, "init #0");
+      if (!EPaperBase::initialise(partial)) {  // Call parent impl
+        return false;                          // If parent should request another loop, do so
+      }
+
+      // Fast init requested + supported?
+      if (partial && (this->fast_update_length_ > 0)) {
+        this->step_ = FSMState::INIT_STEP1_FASTINIT;
+        this->wait_for_idle_(true);  // Must wait for idle before fastinit sequence in next loop
+        return false;                // another loop: step #1 below
+      }
+
+      break;  // End state loop below
+
+    case FSMState::INIT_STEP1_FASTINIT:
+      // Step #1: Fast init sequence
+      ESP_LOGVV(TAG, "init #1");
+      this->write_fastinit_();
+      break;  // End state loop below
+
+    default:
+      // Unexpected step = bug?
+      this->mark_failed();
+  }
+
+  this->step_ = FSMState::NONE;
+  return true;  // Finished: State transition waits for idle
+}
+
+bool EPaperJD79660::transfer_buffer_chunks_() {
+  size_t buf_idx = 0;
+  uint8_t bytes_to_send[MAX_TRANSFER_SIZE];
+  const uint32_t start_time = App.get_loop_component_start_time();
+  const auto buffer_length = this->buffer_length_;
+  while (this->current_data_index_ != buffer_length) {
+    bytes_to_send[buf_idx++] = this->buffer_[this->current_data_index_++];
+
+    if (buf_idx == sizeof bytes_to_send) {
+      this->start_data_();
+      this->write_array(bytes_to_send, buf_idx);
+      this->disable();
+      ESP_LOGVV(TAG, "Wrote %zu bytes at %ums", buf_idx, (unsigned) millis());
+      buf_idx = 0;
+
+      if (millis() - start_time > MAX_TRANSFER_TIME) {
+        // Let the main loop run and come back next loop
+        return false;
+      }
+    }
+  }
+
+  // Finished the entire dataset
+  if (buf_idx != 0) {
+    this->start_data_();
+    this->write_array(bytes_to_send, buf_idx);
+    this->disable();
+    ESP_LOGVV(TAG, "Wrote %zu bytes at %ums", buf_idx, (unsigned) millis());
+  }
+  // Cleanup for next transfer
+  this->current_data_index_ = 0;
+
+  // Finished with all buffer chunks
+  return true;
+}
+
+void EPaperJD79660::write_fastinit_() {
+  // Undocumented register sequence in vendor register range.
+  // Related to Fast Init/Update.
+  // Should likely happen after regular init seq and power on, but before refresh.
+  // Might only work for some models with certain factory MTP.
+  // Please do not change without knowledge to avoid breakage.
+
+  this->send_init_sequence_(this->fast_update_, this->fast_update_length_);
+}
+
+bool EPaperJD79660::transfer_data() {
+  // For now always send full frame buffer in chunks.
+  // JD79660 might support partial window transfers. But sample code missing.
+  // And likely minimal impact, solely on SPI transfer time into RAM.
+
+  if (this->current_data_index_ == 0) {
+    this->command(CMD_TRANSFER);
+  }
+
+  return this->transfer_buffer_chunks_();
+}
+
+void EPaperJD79660::refresh_screen([[maybe_unused]] bool partial) {
+  ESP_LOGV(TAG, "Refresh");
+  this->cmd_data(CMD_REFRESH, {(uint8_t) 0x00});
+}
+
+void EPaperJD79660::power_off() {
+  ESP_LOGV(TAG, "Power off");
+  this->cmd_data(CMD_POWEROFF, {(uint8_t) 0x00});
+}
+
+void EPaperJD79660::deep_sleep() {
+  ESP_LOGV(TAG, "Deep sleep");
+  // "Deepsleep between update": Ensure EPD sleep to avoid early hardware wearout!
+  this->cmd_data(CMD_DEEPSLEEP, {(uint8_t) 0xA5});
+
+  // Notes:
+  // - VDD: Some boards (Waveshare) with "clever reset logic" would allow switching off
+  //   EPD VDD by pulling reset pin low for longer time.
+  //   However, a) not all boards have this, b) reliable sequence timing is difficult,
+  //   c) saving is not worth it after deepsleep command above.
+  //   If needed: Better option is to drive VDD via MOSFET with separate enable pin.
+  //
+  // - Possible safe shutdown:
+  //   EPaperBase::on_safe_shutdown() may also trigger deep_sleep() again.
+  //   Regularly, in IDLE state, this does not make sense for this "deepsleep between update" model,
+  //   but SPI sequence should simply be ignored by sleeping receiver.
+  //   But if triggering during lengthy update, this quick SPI sleep sequence may have benefit.
+  //   Optimally, EPDs should even be set all white for longer storage.
+  //   But full sequence (>15s) not possible w/o app logic.
+}
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/epaper_spi_jd79660.h

@@ -0,0 +1,145 @@
+#pragma once
+
+#include "epaper_spi.h"
+
+namespace esphome::epaper_spi {
+
+/**
+ * JD7966x IC driver implementation
+ *
+ * Currently tested with:
+ * - JD79660 (max res: 200x200)
+ *
+ * May also work for other JD7966x chipset family members with minimal adaptations.
+ *
+ * Capabilities:
+ * - HW frame buffer layout:
+ *   4 colors (gray0..3, commonly BWYR). Bytes consist of 4px/2bpp.
+ *   Width must be rounded to multiple of 4.
+ * - Fast init/update (shorter wave forms): Yes. Controlled by CONF_FULL_UPDATE_EVERY.
+ *   Needs undocumented fastinit sequence, based on likely vendor specific MTP content.
+ * - Partial transfer (transfer only changed window): No. Maybe possible by HW.
+ * - Partial refresh (refresh only changed window): No. Likely HW limit.
+ *
+ * @internal \c final saves few bytes by devirtualization. Remove \c final when subclassing.
+ */
+class EPaperJD79660 final : public EPaperBase {
+ public:
+  EPaperJD79660(const char *name, uint16_t width, uint16_t height, const uint8_t *init_sequence,
+                size_t init_sequence_length, const uint8_t *fast_update, uint16_t fast_update_length)
+      : EPaperBase(name, width, height, init_sequence, init_sequence_length, DISPLAY_TYPE_COLOR),
+        fast_update_(fast_update),
+        fast_update_length_(fast_update_length) {
+    this->row_width_ = (width + 3) / 4;  // Fix base class calc (2bpp instead of 1bpp)
+    this->buffer_length_ = this->row_width_ * height;
+  }
+
+  void fill(Color color) override;
+
+ protected:
+  /** Draw colored pixel into frame buffer */
+  void draw_pixel_at(int x, int y, Color color) override;
+
+  /** Reset (multistep sequence)
+   * @pre this->reset_pin_ != nullptr // cv.Required check
+   * @post Should be idle on successful reset. Can mark failures.
+   */
+  bool reset() override;
+
+  /** Initialise (multistep sequence) */
+  bool initialise(bool partial) override;
+
+  /** Buffer transfer */
+  bool transfer_data() override;
+
+  /** Power on: Already part of init sequence (likely needed there before transferring buffers).
+   * So nothing to do in FSM state.
+   */
+  void power_on() override {}
+
+  /** Refresh screen
+   * @param partial Ignored: Needed earlier in \a ::initialize
+   * @pre Must be idle.
+   * @post Should return to idle later after processing.
+   */
+  void refresh_screen([[maybe_unused]] bool partial) override;
+
+  /** Power off
+   * @pre Must be idle.
+   * @post Should return to idle later after processing.
+   *       (latter will take long period like ~15-20s on actual refresh!)
+   */
+  void power_off() override;
+
+  /** Deepsleep: Must be used to avoid hardware wearout!
+   * @pre Must be idle.
+   * @post Will go busy, and not return idle till ::reset!
+   */
+  void deep_sleep() override;
+
+  /** Internal: Send fast init sequence via undocumented vendor registers
+   * @pre Must be directly after regular ::initialise sequence, before ::transfer_data
+   * @pre Must be idle.
+   * @post Should return to idle later after processing.
+   */
+  void write_fastinit_();
+
+  /** Internal: Send raw buffer in chunks
+   * \retval true Finished
+   * \retval false Loop time elapsed. Need to call again next loop.
+   */
+  bool transfer_buffer_chunks_();
+
+  /** @name IC commands @{ */
+  static constexpr uint8_t CMD_POWEROFF = 0x02;
+  static constexpr uint8_t CMD_DEEPSLEEP = 0x07;
+  static constexpr uint8_t CMD_TRANSFER = 0x10;
+  static constexpr uint8_t CMD_REFRESH = 0x12;
+  /** @} */
+
+  /** State machine constants for \a step_ */
+  enum class FSMState : uint8_t {
+    NONE = 0,  //!< Initial/default value: Unused
+
+    /* Reset state steps */
+    RESET_STEP0_H,
+    RESET_STEP1_L,
+    RESET_STEP2_IDLECHECK,
+
+    /* Init state steps */
+    INIT_STEP0_REGULARINIT,
+    INIT_STEP1_FASTINIT,
+  };
+
+  /** Wait time (millisec) for first reset phase: High
+   *
+   * Wait via FSM loop.
+   */
+  static constexpr uint16_t SLEEP_MS_RESET0 = 200;
+
+  /** Wait time (millisec) for second reset phase: Low
+   *
+   * Holding Reset Low too long may trigger "clever reset" logic
+   * of e.g. Waveshare Rev2 boards: VDD is shut down via MOSFET, and IC
+   * will not report idle anymore!
+   * FSM loop may spuriously increase delay, e.g. >16ms.
+   * Therefore, sync wait below, as allowed (code rule "delays > 10ms not permitted"),
+   * yet only slightly exceeding known IC min req of >1.5ms.
+   */
+  static constexpr uint16_t SLEEP_MS_RESET1 = 2;
+
+  /** Wait time (millisec) for third reset phase: High
+   *
+   * Wait via FSM loop.
+   */
+  static constexpr uint16_t SLEEP_MS_RESET2 = 200;
+
+  // properties initialised in the constructor
+  const uint8_t *const fast_update_{};
+  const uint16_t fast_update_length_{};
+
+  /** Counter for tracking substeps within FSM state */
+  FSMState step_{FSMState::NONE};
+};
+
+}  // namespace esphome::epaper_spi

esphome/components/epaper_spi/models/jd79660.py

@@ -0,0 +1,86 @@
+import esphome.codegen as cg
+from esphome.components.mipi import flatten_sequence
+import esphome.config_validation as cv
+from esphome.const import CONF_BUSY_PIN, CONF_RESET_PIN
+from esphome.core import ID
+
+from ..display import CONF_INIT_SEQUENCE_ID
+from . import EpaperModel
+
+
+class JD79660(EpaperModel):
+    def __init__(self, name, class_name="EPaperJD79660", fast_update=None, **kwargs):
+        super().__init__(name, class_name, **kwargs)
+        self.fast_update = fast_update
+
+    def option(self, name, fallback=cv.UNDEFINED) -> cv.Optional | cv.Required:
+        # Validate required pins, as C++ code will assume existence
+        if name in (CONF_RESET_PIN, CONF_BUSY_PIN):
+            return cv.Required(name)
+
+        # Delegate to parent
+        return super().option(name, fallback)
+
+    def get_constructor_args(self, config) -> tuple:
+        # Resembles init_sequence handling for fast_update config
+        if self.fast_update is None:
+            fast_update = cg.nullptr, 0
+        else:
+            flat_fast_update = flatten_sequence(self.fast_update)
+            fast_update = (
+                cg.static_const_array(
+                    ID(
+                        config[CONF_INIT_SEQUENCE_ID].id + "_fast_update", type=cg.uint8
+                    ),
+                    flat_fast_update,
+                ),
+                len(flat_fast_update),
+            )
+        return (*fast_update,)
+
+
+jd79660 = JD79660(
+    "jd79660",
+    # Specified refresh times are ~20s (full) or ~15s (fast) due to BWRY.
+    # So disallow low update intervals (with safety margin), to avoid e.g. FSM update loops.
+    # Even less frequent intervals (min/h) highly recommended to optimize lifetime!
+    minimum_update_interval="30s",
+    # SPI rate: From spec comparisons, IC should allow SCL write cycles up to 10MHz rate.
+    # Existing code samples also prefer 10MHz. So justifies as default.
+    # Decrease value further in user config if needed (e.g. poor cabling).
+    data_rate="10MHz",
+    # No need to set optional reset_duration:
+    # Code requires multistep reset sequence with precise timings
+    # according to data sheet or samples.
+)
+
+# Waveshare 1.54-G
+#
+# Device may have specific factory provisioned MTP content to facilitate vendor register features like fast init.
+# Vendor specific init derived from vendor sample code
+# <https://github.com/waveshareteam/e-Paper/blob/master/E-paper_Separate_Program/1in54_e-Paper_G/ESP32/EPD_1in54g.cpp>
+# Compatible MIT license, see esphome/LICENSE file.
+#
+# fmt: off
+jd79660.extend(
+    "Waveshare-1.54in-G",
+    width=200,
+    height=200,
+
+    initsequence=(
+        (0x4D, 0x78,),
+        (0x00, 0x0F, 0x29,),
+        (0x06, 0x0d, 0x12, 0x30, 0x20, 0x19, 0x2a, 0x22,),
+        (0x50, 0x37,),
+        (0x61, 200 // 256, 200 % 256, 200 // 256, 200 % 256,),  # RES: 200x200 fixed
+        (0xE9, 0x01,),
+        (0x30, 0x08,),
+        # Power On (0x04): Must be early part of init seq = Disabled later!
+        (0x04,),
+    ),
+    fast_update=(
+        (0xE0, 0x02,),
+        (0xE6, 0x5D,),
+        (0xA5, 0x00,),
+    ),
+)

esphome/components/template/water_heater/__init__.py

@@ -46,6 +46,7 @@ CONFIG_SCHEMA = (
                 RESTORE_MODES, upper=True
             ),
             cv.Optional(CONF_CURRENT_TEMPERATURE): cv.returning_lambda,
+            cv.Optional(CONF_TARGET_TEMPERATURE): cv.returning_lambda,
             cv.Optional(CONF_MODE): cv.returning_lambda,
             cv.Optional(CONF_SUPPORTED_MODES): cv.ensure_list(
                 water_heater.validate_water_heater_mode
@@ -78,6 +79,14 @@ async def to_code(config: ConfigType) -> None:
         )
         cg.add(var.set_current_temperature_lambda(template_))
 
+    if CONF_TARGET_TEMPERATURE in config:
+        template_ = await cg.process_lambda(
+            config[CONF_TARGET_TEMPERATURE],
+            [],
+            return_type=cg.optional.template(cg.float_),
+        )
+        cg.add(var.set_target_temperature_lambda(template_))
+
     if CONF_MODE in config:
         template_ = await cg.process_lambda(
             config[CONF_MODE],

esphome/components/template/water_heater/template_water_heater.cpp

@@ -16,7 +16,8 @@ void TemplateWaterHeater::setup() {
       restore->perform();
     }
   }
-  if (!this->current_temperature_f_.has_value() && !this->mode_f_.has_value())
+  if (!this->current_temperature_f_.has_value() && !this->target_temperature_f_.has_value() &&
+      !this->mode_f_.has_value())
     this->disable_loop();
 }
 
@@ -28,6 +29,9 @@ water_heater::WaterHeaterTraits TemplateWaterHeater::traits() {
   }
 
   traits.set_supports_current_temperature(true);
+  if (this->target_temperature_f_.has_value()) {
+    traits.add_feature_flags(water_heater::WATER_HEATER_SUPPORTS_TARGET_TEMPERATURE);
+  }
   return traits;
 }
 
@@ -42,6 +46,14 @@ void TemplateWaterHeater::loop() {
     }
   }
 
+  auto target_temp = this->target_temperature_f_.call();
+  if (target_temp.has_value()) {
+    if (*target_temp != this->target_temperature_) {
+      this->target_temperature_ = *target_temp;
+      changed = true;
+    }
+  }
+
   auto new_mode = this->mode_f_.call();
   if (new_mode.has_value()) {
     if (*new_mode != this->mode_) {

esphome/components/template/water_heater/template_water_heater.h

@@ -20,6 +20,9 @@ class TemplateWaterHeater : public Component, public water_heater::WaterHeater {
   template<typename F> void set_current_temperature_lambda(F &&f) {
     this->current_temperature_f_.set(std::forward<F>(f));
   }
+  template<typename F> void set_target_temperature_lambda(F &&f) {
+    this->target_temperature_f_.set(std::forward<F>(f));
+  }
   template<typename F> void set_mode_lambda(F &&f) { this->mode_f_.set(std::forward<F>(f)); }
 
   void set_optimistic(bool optimistic) { this->optimistic_ = optimistic; }
@@ -44,6 +47,7 @@ class TemplateWaterHeater : public Component, public water_heater::WaterHeater {
   // Ordered to minimize padding on 32-bit: 4-byte members first, then smaller
   Trigger<> set_trigger_;
   TemplateLambda<float> current_temperature_f_;
+  TemplateLambda<float> target_temperature_f_;
   TemplateLambda<water_heater::WaterHeaterMode> mode_f_;
   TemplateWaterHeaterRestoreMode restore_mode_{WATER_HEATER_NO_RESTORE};
   water_heater::WaterHeaterModeMask supported_modes_;

esphome/dashboard/web_server.py

@@ -317,6 +317,7 @@ class EsphomeCommandWebSocket(CheckOriginMixin, tornado.websocket.WebSocketHandl
             # Check if the proc was not forcibly closed
             _LOGGER.info("Process exited with return code %s", returncode)
             self.write_message({"event": "exit", "code": returncode})
+            self.close()
 
     def on_close(self) -> None:
         # Check if proc exists (if 'start' has been run)

tests/components/epaper_spi/test.esp32-s3-idf.yaml

@@ -25,6 +25,22 @@ display:
     lambda: |-
       it.circle(64, 64, 50, Color::BLACK);
 
+  - platform: epaper_spi
+    spi_id: spi_bus
+    model: waveshare-1.54in-G
+    cs_pin:
+      allow_other_uses: true
+      number: GPIO5
+    dc_pin:
+      allow_other_uses: true
+      number: GPIO17
+    reset_pin:
+      allow_other_uses: true
+      number: GPIO16
+    busy_pin:
+      allow_other_uses: true
+      number: GPIO4
+
   - platform: epaper_spi
     spi_id: spi_bus
     model: waveshare-2.13in-v3

tests/components/template/common-base.yaml

@@ -412,6 +412,7 @@ water_heater:
     name: "Template Water Heater"
     optimistic: true
     current_temperature: !lambda "return 42.0f;"
+    target_temperature: !lambda "return 60.0f;"
     mode: !lambda "return water_heater::WATER_HEATER_MODE_ECO;"
     supported_modes:
       - "OFF"

tests/dashboard/test_web_server.py

@@ -29,7 +29,7 @@ from esphome.dashboard.entries import (
     bool_to_entry_state,
 )
 from esphome.dashboard.models import build_importable_device_dict
-from esphome.dashboard.web_server import DashboardSubscriber
+from esphome.dashboard.web_server import DashboardSubscriber, EsphomeCommandWebSocket
 from esphome.zeroconf import DiscoveredImport
 
 from .common import get_fixture_path
@@ -1654,3 +1654,25 @@ async def test_websocket_check_origin_multiple_trusted_domains(
             assert data["event"] == "initial_state"
         finally:
             ws.close()
+
+
+def test_proc_on_exit_calls_close() -> None:
+    """Test _proc_on_exit sends exit event and closes the WebSocket."""
+    handler = Mock(spec=EsphomeCommandWebSocket)
+    handler._is_closed = False
+
+    EsphomeCommandWebSocket._proc_on_exit(handler, 0)
+
+    handler.write_message.assert_called_once_with({"event": "exit", "code": 0})
+    handler.close.assert_called_once()
+
+
+def test_proc_on_exit_skips_when_already_closed() -> None:
+    """Test _proc_on_exit does nothing when WebSocket is already closed."""
+    handler = Mock(spec=EsphomeCommandWebSocket)
+    handler._is_closed = True
+
+    EsphomeCommandWebSocket._proc_on_exit(handler, 0)
+
+    handler.write_message.assert_not_called()
+    handler.close.assert_not_called()

tests/integration/fixtures/water_heater_template.yaml

@@ -10,6 +10,7 @@ water_heater:
     name: Test Boiler
     optimistic: true
     current_temperature: !lambda "return 45.0f;"
+    target_temperature: !lambda "return 60.0f;"
     # Note: No mode lambda - we want optimistic mode changes to stick
     # A mode lambda would override mode changes in loop()
     supported_modes:

tests/integration/test_water_heater_template.py

@@ -85,6 +85,9 @@ async def test_water_heater_template(
         assert initial_state.current_temperature == 45.0, (
             f"Expected current temp 45.0, got {initial_state.current_temperature}"
         )
+        assert initial_state.target_temperature == 60.0, (
+            f"Expected target temp 60.0, got {initial_state.target_temperature}"
+        )
 
         # Test changing to GAS mode
         client.water_heater_command(test_water_heater.key, mode=WaterHeaterMode.GAS)