Adds new lint function for empty env files

New function that raises a failure if the size of
the environment file, if this one exists, is zero.

Signed-off-by: mcasquer <[email protected]>

docs/releases.rst

@@ -70,6 +70,8 @@ The :ref:`/plugins/report/reportportal` plugin now uploads the
 complete set of discovered tests, including those which have not
 been executed. These tests are marked as ``skipped``.
 
+``tmt lint`` now reports a failure if empty environment files are found.
+
 
 tmt-1.36.1
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

tmt/base.py

@@ -2332,6 +2332,23 @@ def _lint_step(step: str) -> LinterReturn:
         yield from _lint_step('execute')
         yield from _lint_step('finish')
 
+    def lint_empty_env_files(self) -> LinterReturn:
+        """ P008: env files are not empty """
+
+        env_files = self.node.get("environment-file") or []
+
+        if not env_files:
+            yield LinterOutcome.SKIP, 'no environment files found'
+            return
+
+        for env_file in env_files:
+            env_file = Path(env_file).resolve()
+            if not env_file.stat().st_size:
+                yield LinterOutcome.FAIL, f'the file "{env_file}" is empty'
+                return
+
+        yield LinterOutcome.PASS, 'no empty environment files'
+
     def wake(self) -> None:
         """ Wake up all steps """