Add enable-warnings-report option

It's necessary to clear the cache between each compilation to get a true compiler warning count,
otherwise only the first sketch compilation's warning count would reflect warnings from cached code.

However, deleting the cache means the code must be completely compiled every time. This increases
the duration of the compilations, so it should only be done when the compiler warnings count is wanted.
For this reason, it was necessary to add an input to control this behavior.

Author: per1234

README.md

@@ -118,7 +118,11 @@ GitHub access token used to get information from the GitHub API. Only needed for
 
 ### `enable-deltas-report`
 
-Set to `true` to cause the action to determine the change in memory usage and compiler warnings of the compiled sketches. If the workflow is triggered by a `pull_request` event, the comparison is between the pull request branch and the tip of the pull request's base branch. If the workflow is triggered by a `push` event, the comparison is between the pushed commit and its immediate parent. This may be used with the [`arduino/actions/libraries/report-size-deltas` action](https://github.com/arduino/actions/tree/master/libraries/report-size-deltas). Default `false`.
+Set to `true` to cause the action to determine the change in memory usage and compiler warnings of the compiled sketches. If the workflow is triggered by a `pull_request` event, the comparison is between the pull request branch and the tip of the pull request's base branch. If the workflow is triggered by a `push` event, the comparison is between the pushed commit and its immediate parent. The deltas will be displayed in the GitHub Actions build log. This may be used with the [`arduino/actions/libraries/report-size-deltas` action](https://github.com/arduino/actions/tree/master/libraries/report-size-deltas). Default `false`.
+
+### `enable-warnings-report`
+
+Set to `true` to cause the action to record the compiler warning count for each sketch compilation in the sketches report. Default `false`.
 
 ## Example usage
 

action.yml

@@ -28,6 +28,10 @@ inputs:
   enable-deltas-report:
     description: 'Set to true to cause the action to determine the change in memory usage and compiler warnings of the compiled sketches between the head and base refs of a PR and the immediate parent commit of a push'
     default: false
+  enable-warnings-report:
+    description: 'Set to true to cause the action to record the compiler warning count for each sketch compilation in the sketches report'
+    default: false
+
 runs:
   using: 'docker'
   image: 'Dockerfile'

compilesketches/compilesketches.py

@@ -46,6 +46,7 @@ def main():
         verbose=os.environ["INPUT_VERBOSE"],
         github_token=os.environ["INPUT_GITHUB-TOKEN"],
         enable_deltas_report=os.environ["INPUT_ENABLE-DELTAS-REPORT"],
+        enable_warnings_report=os.environ["INPUT_ENABLE-WARNINGS-REPORT"],
         sketches_report_path=os.environ["INPUT_SKETCHES-REPORT-PATH"]
     )
 
@@ -67,6 +68,8 @@ class CompileSketches:
     github_token -- GitHub access token
     enable_deltas_report -- set to "true" to cause the action to determine the change in memory usage
                                  ("true", "false")
+    enable_warnings_report -- set to "true" to cause the action to add compiler warning count to the sketches report
+                                 ("true", "false")
     sketches_report_path -- folder to save the sketches report to
     """
 
@@ -112,7 +115,7 @@ class ReportKeys:
     latest_release_indicator = "latest"
 
     def __init__(self, cli_version, fqbn_arg, platforms, libraries, sketch_paths, verbose, github_token,
-                 enable_deltas_report, sketches_report_path):
+                 enable_deltas_report, enable_warnings_report, sketches_report_path):
         """Process, store, and validate the action's inputs."""
         self.cli_version = cli_version
 
@@ -141,6 +144,12 @@ def __init__(self, cli_version, fqbn_arg, platforms, libraries, sketch_paths, ve
             print("::error::Invalid value for enable-deltas-report input")
             sys.exit(1)
 
+        self.enable_warnings_report = parse_boolean_input(boolean_input=enable_warnings_report)
+        # The enable-deltas-report input has a default value so it should always be either True or False
+        if self.enable_warnings_report is None:
+            print("::error::Invalid value for enable-warnings-report input")
+            sys.exit(1)
+
         if self.enable_deltas_report:
             self.deltas_base_ref = self.get_deltas_base_ref()
         else:
@@ -191,7 +200,9 @@ def compile_sketches(self):
 
         sketch_list = self.find_sketches()
         for sketch in sketch_list:
-            compilation_result = self.compile_sketch(sketch_path=sketch)
+            # It's necessary to clear the cache between each compilation to get a true compiler warning count, otherwise
+            # only the first sketch compilation's warning count would reflect warnings from cached code
+            compilation_result = self.compile_sketch(sketch_path=sketch, clean_build_cache=self.enable_warnings_report)
             if not compilation_result.success:
                 all_compilations_successful = False
 
@@ -851,17 +862,22 @@ def find_sketches(self):
 
         return sketch_list
 
-    def compile_sketch(self, sketch_path):
+    def compile_sketch(self, sketch_path, clean_build_cache):
         """Compile the specified sketch and returns an object containing the result:
         sketch -- the sketch path relative to the workspace
         success -- the success of the compilation (True, False)
         output -- stdout from Arduino CLI
 
         Keyword arguments:
         sketch_path -- path of the sketch to compile
+        clean_build_cache -- whether to delete cached compiled from previous compilations before compiling
         """
         compilation_command = ["compile", "--warnings", "all", "--fqbn", self.fqbn, sketch_path]
 
+        if clean_build_cache:
+            for cache_path in pathlib.Path("/tmp").glob(pattern="arduino*"):
+                shutil.rmtree(path=cache_path)
+
         compilation_data = self.run_arduino_cli_command(
             command=compilation_command, enable_output=self.RunCommandOutput.NONE, exit_on_failure=False)
         # Group compilation output to make the log easy to read
@@ -887,8 +903,10 @@ def get_sketch_report(self, compilation_result):
         compilation_result -- object returned by compile_sketch()
         """
         current_sizes = self.get_sizes_from_output(compilation_result=compilation_result)
-        current_warning_count = self.get_warning_count_from_output(compilation_result=compilation_result)
-
+        if self.enable_warnings_report:
+            current_warning_count = self.get_warning_count_from_output(compilation_result=compilation_result)
+        else:
+            current_warning_count = None
         previous_sizes = None
         previous_warning_count = None
         if self.do_deltas_report(compilation_result=compilation_result,
@@ -904,23 +922,30 @@ def get_sketch_report(self, compilation_result):
 
             # Compile the sketch again
             print("Compiling previous version of sketch to determine memory usage change")
-            previous_compilation_result = self.compile_sketch(sketch_path=compilation_result.sketch)
+            previous_compilation_result = self.compile_sketch(sketch_path=compilation_result.sketch,
+                                                              clean_build_cache=self.enable_warnings_report)
 
             # git checkout the head ref to return the repository to its previous state
             repository.git.checkout(original_git_ref, recurse_submodules=True)
 
             previous_sizes = self.get_sizes_from_output(compilation_result=previous_compilation_result)
-            previous_warning_count = self.get_warning_count_from_output(compilation_result=previous_compilation_result)
+            if self.enable_warnings_report:
+                previous_warning_count = (
+                    self.get_warning_count_from_output(compilation_result=previous_compilation_result)
+                )
 
         # Add global data for sketch to report
         sketch_report = {
             self.ReportKeys.name: str(path_relative_to_workspace(path=compilation_result.sketch)),
             self.ReportKeys.compilation_success: compilation_result.success,
             self.ReportKeys.sizes: self.get_sizes_report(current_sizes=current_sizes,
                                                          previous_sizes=previous_sizes),
-            self.ReportKeys.warnings: self.get_warnings_report(current_warnings=current_warning_count,
-                                                               previous_warnings=previous_warning_count)
         }
+        if self.enable_warnings_report:
+            sketch_report[self.ReportKeys.warnings] = (
+                self.get_warnings_report(current_warnings=current_warning_count,
+                                         previous_warnings=previous_warning_count)
+            )
 
         return sketch_report
 
@@ -1046,7 +1071,10 @@ def do_deltas_report(self, compilation_result, current_sizes, current_warnings):
             and (
                 any(size.get(self.ReportKeys.absolute) != self.not_applicable_indicator for
                     size in current_sizes)
-                or current_warnings != self.not_applicable_indicator
+                or (
+                    current_warnings is not None
+                    and current_warnings != self.not_applicable_indicator
+                )
             )
         )
 
@@ -1318,7 +1346,10 @@ def get_warnings_summary_report(self, sketch_report_list):
         summary_report_minimum = None
         summary_report_maximum = None
         for sketch_report in sketch_report_list:
-            if self.ReportKeys.delta in sketch_report[self.ReportKeys.warnings]:
+            if (
+                self.ReportKeys.warnings in sketch_report
+                and self.ReportKeys.delta in sketch_report[self.ReportKeys.warnings]
+            ):
                 sketch_report_delta = (
                     sketch_report[self.ReportKeys.warnings][self.ReportKeys.delta][self.ReportKeys.absolute]
                 )