Revert "Tools: Don't check Python packages on every idf.py & cmake run"

This reverts commit 0265c79bcc.

tools/cmake/build.cmake

@@ -273,6 +273,27 @@ function(__build_write_properties output_file)
     file(WRITE ${output_file} "${build_properties_text}")
 endfunction()
 
+#
+# Check if the Python interpreter used for the build has all the required modules.
+#
+function(__build_check_python)
+    idf_build_get_property(check __CHECK_PYTHON)
+    if(check)
+        idf_build_get_property(python PYTHON)
+        idf_build_get_property(idf_path IDF_PATH)
+        message(STATUS "Checking Python dependencies...")
+        execute_process(COMMAND "${python}" "${idf_path}/tools/idf_tools.py" "check-python-dependencies"
+            RESULT_VARIABLE result)
+        if(result EQUAL 1)
+            # check_python_dependencies returns error code 1 on failure
+            message(FATAL_ERROR "Some Python dependencies must be installed. Check above message for details.")
+        elseif(NOT result EQUAL 0)
+            # means check_python_dependencies.py failed to run at all, result should be an error message
+            message(FATAL_ERROR "Failed to run Python dependency check. Python: ${python}, Error: ${result}")
+        endif()
+    endif()
+endfunction()
+
 #
 # Prepare for component processing expanding each component's project include
 #
@@ -393,6 +414,9 @@ macro(idf_build_process target)
 
     __build_set_default(SDKCONFIG_DEFAULTS "")
 
+    # Check for required Python modules
+    __build_check_python()
+
     idf_build_get_property(target IDF_TARGET)
 
     if(NOT "${target}" STREQUAL "linux")

tools/idf.py

@@ -89,6 +89,24 @@ def check_environment():
     except RuntimeError as e:
         raise FatalError(e)
 
+    # check Python dependencies
+    checks_output.append('Checking Python dependencies...')
+    try:
+        out = subprocess.check_output(
+            [
+                os.environ['PYTHON'],
+                os.path.join(os.environ['IDF_PATH'], 'tools', 'idf_tools.py'),
+                'check-python-dependencies',
+            ],
+            env=os.environ,
+        )
+
+        checks_output.append(out.decode('utf-8', 'ignore').strip())
+    except subprocess.CalledProcessError as e:
+        print_warning(e.output.decode('utf-8', 'ignore'), stream=sys.stderr)
+        debug_print_idf_version()
+        raise SystemExit(1)
+
     return checks_output