twister: Collect test names in lcov

When using --coverage-per-instance, collect the test names in lcov, and
add --show-details to the html report to display those test names.

Signed-off-by: Jeremy Bettis <[email protected]>

Author: jeremybettis

scripts/pylib/twister/twisterlib/coverage.py

@@ -297,6 +297,10 @@ def _generate(self, outdir, coveragelog, build_dirs=None):
                 cmd.append(filename)
         else:
             cmd = ["--capture", "--directory", outdir, "--output-file", coveragefile]
+            if self.coverage_per_instance and len(self.instances) == 1:
+                invalid_chars = re.compile(r"[^A-Za-z0-9_]")
+                cmd.append("--test-name")
+                cmd.append(invalid_chars.sub("_", next(iter(self.instances))))
         self.run_lcov(cmd, coveragelog)
 
         # We want to remove tests/* and tests/ztest/test/* but save tests/ztest
@@ -325,7 +329,10 @@ def _generate(self, outdir, coveragelog, build_dirs=None):
 
         cmd = ["genhtml", "--legend", "--branch-coverage",
                "--prefix", self.base_dir,
-               "-output-directory", os.path.join(outdir, "coverage")] + files
+               "-output-directory", os.path.join(outdir, "coverage")]
+        if self.coverage_per_instance:
+            cmd.append("--show-details")
+        cmd += files
         ret = self.run_command(cmd, coveragelog)
 
         # TODO: Add LCOV summary coverage report.