[core] Add helper functions for clamp_at_... (#10387)

esphome/core/helpers.h

@@ -12,6 +12,7 @@
 #include <string>
 #include <type_traits>
 #include <vector>
+#include <concepts>
 
 #include "esphome/core/optional.h"
 
@@ -1169,7 +1170,20 @@ template<class T> class RAMAllocator {
 
 template<class T> using ExternalRAMAllocator = RAMAllocator<T>;
 
-/// @}
+/**
+ * Functions to constrain the range of arithmetic values.
+ */
+
+template<std::totally_ordered T> T clamp_at_least(T value, T min) {
+  if (value < min)
+    return min;
+  return value;
+}
+template<std::totally_ordered T> T clamp_at_most(T value, T max) {
+  if (value > max)
+    return max;
+  return value;
+}
 
 /// @name Internal functions
 ///@{

tests/components/esp32/common.yaml

@@ -0,0 +1,13 @@
+logger:
+  level: VERBOSE
+
+esphome:
+  on_boot:
+    - lambda: |-
+        int x = 100;
+        x = clamp(x, 50, 90);
+        assert(x == 90);
+        x = clamp_at_least(x, 95);
+        assert(x == 95);
+        x = clamp_at_most(x, 40);
+        assert(x == 40);

tests/components/esp8266/test.esp8266-ard.yaml

@@ -0,0 +1,13 @@
+logger:
+  level: VERBOSE
+
+esphome:
+  on_boot:
+    - lambda: |-
+        int x = 100;
+        x = clamp(x, 50, 90);
+        assert(x == 90);
+        x = clamp_at_least(x, 95);
+        assert(x == 95);
+        x = clamp_at_most(x, 40);
+        assert(x == 40);

tests/components/host/common.yaml

@@ -15,3 +15,10 @@ esphome:
         static const uint8_t my_addr[6] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
         if (!mac_address_is_valid(my_addr))
           ESP_LOGD("test", "Invalid mac address %X", my_addr[0]); // etc.
+        int x = 100;
+        x = clamp(x, 50, 90);
+        assert(x == 90);
+        x = clamp_at_least(x, 95);
+        assert(x == 95);
+        x = clamp_at_most(x, 40);
+        assert(x == 40);

tests/components/libretiny/test.bk72xx-ard.yaml

@@ -0,0 +1,13 @@
+logger:
+  level: VERBOSE
+
+esphome:
+  on_boot:
+    - lambda: |-
+        int x = 100;
+        x = clamp(x, 50, 90);
+        assert(x == 90);
+        x = clamp_at_least(x, 95);
+        assert(x == 95);
+        x = clamp_at_most(x, 40);
+        assert(x == 40);

tests/components/nrf52/test.nrf52-adafruit.yaml

@@ -1,3 +1,13 @@
+esphome:
+  on_boot:
+    - lambda: |-
+        int x = 100;
+        x = clamp(x, 50, 90);
+        assert(x == 90);
+        x = clamp_at_least(x, 95);
+        assert(x == 95);
+        x = clamp_at_most(x, 40);
+        assert(x == 40);
 nrf52:
   dfu:
     reset_pin:

tests/components/rp2040/test.rp2040-ard.yaml

@@ -0,0 +1,13 @@
+logger:
+  level: VERBOSE
+
+esphome:
+  on_boot:
+    - lambda: |-
+        int x = 100;
+        x = clamp(x, 50, 90);
+        assert(x == 90);
+        x = clamp_at_least(x, 95);
+        assert(x == 95);
+        x = clamp_at_most(x, 40);
+        assert(x == 40);