Refactor: Separate non-language-specific implementations (#29)

bzl_internal/general_build_actions.bzl

@@ -0,0 +1,134 @@
+"""Implementations for non-langage-specific build actions.
+"""
+
+visibility("//lang/...")
+
+# Default value of matcher struct passed to each message assertion.
+DEFAULT_MATCHER = struct(
+    matcher = None,
+    pattern = None,
+)
+
+def get_executable_file(label):
+    """Get executable file if the label is not None.
+
+    Args:
+        label(label or None): Executable label
+
+    Returns:
+        File: Executable file.
+    """
+    if not label:
+        return None
+    return label.files_to_run.executable
+
+def check_build_error(
+        *,
+        ctx,
+        files_to_check,
+        error_message,
+        check_emptiness):
+    """Check if a build error occured.
+
+    Force internal `ctx.actions.run` execution to fail if the previous build error
+    did NOT occur, otherwise, create an empty text file as a marker for the action.
+    This marker file has to be surely evaluated by the rule.
+
+    Args:
+        ctx(ctx): The rule's context.
+        files_to_check(list[File]): Output of the previous build actions.
+        error_message(str): Error message when the validation fails
+        check_emptiness(File): Executable file object of `check_emptiness.bash`.
+
+    Returns:
+        File: Marker file for the check.
+    """
+
+    # Marker file for the check
+    marker_check_build_error = ctx.actions.declare_file(
+        ctx.label.name + "/marker_check_build_error",
+    )
+
+    # Arguments for `check_emptiness`
+    args = ctx.actions.args()
+
+    for file_to_check in files_to_check:
+        args.add("-f", file_to_check)
+
+    args.add("-m", error_message)
+    args.add("-n", marker_check_build_error)
+
+    ctx.actions.run(
+        outputs = [marker_check_build_error],
+        inputs = files_to_check,
+        executable = check_emptiness,
+        arguments = [args],
+    )
+
+    return marker_check_build_error
+
+def check_each_message(
+        *,
+        ctx,
+        message_file,
+        matcher,
+        pattern,
+        checker):
+    """Check each message with a matcher and a pattern string.
+
+    After checking the message, create an empty text file as a marker for the action.
+    This marker file has to be surely evaluated by the rule.
+
+    Args:
+        ctx(ctx): The rule's context.
+        message_file(File): A text file containing message.
+        matcher(File): A matcher executable.
+        pattern(str): A pattern string.
+        checker(File): Executable file object for `check_each_message.bash`
+
+    Returns:
+        File: Marker file for the check.
+    """
+    marker_file = ctx.actions.declare_file(
+        ctx.label.name +
+        "/marker_check_each_message__" +
+        message_file.basename + "__" +
+        (matcher.path if matcher else "NONE") + "__" +
+        (pattern if pattern else "NONE") + "__",
+    )
+
+    if not matcher:
+        if pattern:
+            fail(
+                "When not specifying the matcher, " +
+                "pattern string must be empty",
+            )
+
+        ctx.actions.run(
+            outputs = [marker_file],
+            executable = "touch",
+            arguments = [
+                marker_file.path,
+            ],
+        )
+    else:
+        if not pattern:
+            fail(
+                "When specifying the matcher, " +
+                "pattern string must not be empty",
+            )
+
+        ctx.actions.run(
+            outputs = [marker_file],
+            inputs = [message_file],
+            executable = checker,
+            arguments = [
+                matcher.path,
+                pattern,
+                message_file.path,
+                marker_file.path,
+            ],
+            tools = [matcher],
+        )
+
+    return marker_file