coverage.py: Add script to process code coverage

This script ease the generation of code coverage report. A report
is based on a codebase, note files (generated at compilation) and
data files (generated at runtime).
The report is generated using lcov and present the code coverage as
a percentage of lines executed compared to the total number of lines
in the codebase.

The script will copy all the note and data files in a temporary
directory allowing to reuse the generated artifact and checks that
the note and data file are correctly organised (the files must be
in the same directory).

The script also allow to generate an html output using genhtml and
to view it.

Signed-off-by: Franck LENORMAND <franck.lenormand@nxp.com>

scripts/coverage.py

@@ -0,0 +1,230 @@
+#!/usr/bin/env python3
+
+# This script will create the coverage report given the coverage notes and data
+
+import sys  # Handle exit status
+import os  # Interact with PATH env variable and filesystem
+import argparse  # Handle command line
+import logging  # Logging
+import distutils.dir_util  # Copy of tree
+import subprocess  # Call lcov and genhtml
+from pathlib import Path  # Glob on gcda and gcno
+
+
+def find_binary(logger, bin_name, proposed_bin_path):
+    """
+    Finds a binary.
+
+    :param      bin_name:  The bin name
+    :type       bin_name:  string
+
+    Return the path to the binary
+    """
+
+    # Check path passed as argument
+    if proposed_bin_path is not None:
+        if os.path.isfile(proposed_bin_path):
+            return proposed_bin_path
+
+    # Get PATH variable
+    pathvar = os.environ['PATH']
+    paths = pathvar.split(os.pathsep)
+
+    # Loop through paths
+    for path in paths:
+        filepath = os.path.join(path, bin_name)
+
+        # Try to find the file
+        if os.path.isfile(filepath):
+            return filepath
+
+    logger.warning("Could not find {} in {}".format(bin_name, paths))
+
+    # Raise exception
+    raise FileNotFoundError('{}'.format(bin_name))
+
+
+def main():
+    cwd = os.getcwd()
+
+    logging.basicConfig(level=logging.INFO)
+    logger = logging.getLogger("coverage")
+
+    default_gcov = "gcov"
+    default_lcov = "lcov"
+    default_genhtml = "genhtml"
+    default_browser = "firefox"
+
+    p = argparse.ArgumentParser(description='Process coverage data generated \
+                                to create coverage result along with an HTML \
+                                output')
+
+    g1 = p.add_argument_group("Information about the analysis")
+    g1.add_argument("--uc", help="Name of the Use Case", type=str,
+                    default="my_uc")
+    g1.add_argument("--info", help="Name of the info file to create", type=str)
+    g1.add_argument("--outdir", help="Path to the directory for analysis",
+                    type=str)
+    g1.add_argument("--html", help="Generate HTML output", action='store_true')
+    g1.add_argument("--view", help="View HTML output in browser",
+                    action='store_true')
+    g1.add_argument("--src_dir", help="Top dir of the sources", type=str,
+                    required=True)
+
+    g2 = p.add_argument_group("Coverage material generated")
+    g2.add_argument("--notes", help="Directory containing the coverage notes",
+                    type=str, required=True)
+    g2.add_argument("--data", help="Directory containing the coverage data",
+                    type=str, required=True)
+
+    g3 = p.add_argument_group("External tools")
+    g3.add_argument("--gcov", help="Path to the gcov binary", type=str,
+                    default=default_gcov)
+    g3.add_argument("--lcov", help="Path to lcov binary", type=str,
+                    default=default_lcov)
+    g3.add_argument("--genhtml", help="Path to genhtml binary", type=str,
+                    default=default_genhtml)
+    g3.add_argument("--browser", help="Path to browser binary", type=str,
+                    default=default_browser)
+
+    p.add_argument("-v", "--verbose", help="verbose mode", action='store_true')
+
+    # Parse the command line
+    args = p.parse_args()
+
+    if args.verbose:
+        logger.setLevel(logging.DEBUG)
+
+    logger.debug("Check analysis parameters")
+    logger.info("Use case name: {}".format(args.uc))
+
+    dir_analysis = (args.outdir if args.outdir is not None
+                    else "{}/{}".format(cwd, args.uc))
+    logger.info("Analysis directory: {}".format(dir_analysis))
+
+    info_filename = (args.info if args.info is not None
+                     else "{}.info".format(args.uc))
+    logger.info("Information filename: {}".format(info_filename))
+
+    info_filepath = "{}/{}".format(dir_analysis, info_filename)
+
+    logger.debug("Check coverage notes directory")
+    if not os.path.isdir(args.notes):
+        raise NotADirectoryError(args.notes)
+    logger.info("Directory containing notes: {}".format(args.notes))
+
+    logger.debug("Check coverage data directory")
+    if not os.path.isdir(args.data):
+        raise NotADirectoryError(args.data)
+    logger.info("Directory containing data: {}".format(args.data))
+
+    logger.debug("Check source directory")
+    if not os.path.isdir(args.src_dir):
+        raise NotADirectoryError(args.src_dir)
+    logger.info("Directory of sources: {}".format(args.src_dir))
+
+    logger.debug("Check external tools")
+    logger.debug("Set gcov binary")
+    gcov_bin = find_binary(l, default_gcov, args.gcov)
+    logger.info("Binary for gcov: {}".format(gcov_bin))
+
+    logger.debug("Set lcov binary")
+    lcov_bin = find_binary(l, default_lcov, args.lcov)
+    logger.info("Binary for lcov: {}".format(lcov_bin))
+
+    if args.html:
+        logger.debug("Set genhtml binary")
+        genhtml_bin = find_binary(l, default_genhtml, args.genhtml)
+        logger.info("Binary for genhtml: {}".format(genhtml_bin))
+
+        if args.view:
+            logger.debug("Set browser binary")
+            browser_bin = find_binary(l, default_browser, args.genhtml)
+            logger.info("Binary for genhtml: {}".format(genhtml_bin))
+
+    logger.debug("Create analysis directory")
+    os.mkdir(dir_analysis)
+    logger.info("Analysis directory: {}".format(dir_analysis))
+
+    logger.debug("Copy notes")
+    distutils.dir_util.copy_tree(args.notes, dir_analysis)
+    logger.debug("Copy notes done")
+
+    logger.debug("Copy data")
+    distutils.dir_util.copy_tree(args.data, dir_analysis)
+    logger.debug("Copy data done")
+
+    logger.debug("Check that the gcno are along the gcda")
+    logger.debug("Search for all the gcda")
+    gcda_files = list(Path(dir_analysis).rglob('*.gcda'))
+
+    if not gcda_files:
+        raise FileNotFoundError("No gcda files can be found in {}".
+                                format(dir_analysis))
+
+    for gcda_file in gcda_files:
+        component = Path(gcda_file).with_suffix('')
+        gcno_file_exp = str(component) + ".gcno"
+        logger.debug("gcda: {}, looking for {}".format(gcda_file,
+                     gcno_file_exp))
+
+        if not os.path.isfile(gcno_file_exp):
+            logger.error("{} does not exists".format(gcno_file_exp))
+            gcno_file = os.path.basename(gcno_file_exp)
+            gcno_files = list(Path(dir_analysis).rglob(gcno_file))
+
+            if not gcno_files:
+                raise FileNotFoundError("{} could not be found in {}".
+                                        format(gcno_file, dir_analysis))
+            else:
+                raise FileNotFoundError('{} not along {}, located at {}'.
+                                        format(gcno_file_exp, gcda_file,
+                                               gcno_files[0]))
+
+    run_analysis_cmd = [lcov_bin, "--capture", "--directory", dir_analysis,
+                        "--gcov-tool", gcov_bin, "--output-file",
+                        info_filepath]
+    logger.debug("Analysis command: {}".format(run_analysis_cmd))
+
+    logger.debug("Run the analysis")
+    run_analysis = subprocess.check_output(run_analysis_cmd,
+                                           stderr=subprocess.STDOUT)
+
+    gcov_errors = ["skipping", "did not produce any data for"]
+
+    logger.debug("Check analysis output")
+    for line in run_analysis.decode("utf-8").splitlines():
+        for error in gcov_errors:
+            if error in line:
+                raise RuntimeError(line)
+
+    logger.info("Analysis done, information file: {}".format(info_filepath))
+
+    if args.html:
+        html_folder = "{}/html".format(dir_analysis)
+
+        generate_html_cmd = [genhtml_bin, "--prefix", args.src_dir, "--legend",
+                             "--title", args.uc, "--output-directory",
+                             html_folder, info_filepath]
+        logger.debug("HTML generation command: {}".format(run_analysis_cmd))
+
+        logger.debug("Create HTML output")
+        generate_html = subprocess.check_output(generate_html_cmd)
+
+        logger.info("HTML generation done, output: {}".format(html_folder))
+
+        html_index = "{}/index.html".format(html_folder)
+        logger.info("HTML index file: {}".format(html_index))
+
+        if args.view:
+            view_cmd = [browser_bin, html_index]
+
+            logger.debug("Show HTML output in browser")
+            logger.info("View HTML in browser: {}".format(view_cmd))
+            subprocess.run(view_cmd)
+
+    sys.exit(0)
+
+
+if __name__ == "__main__":
+    main()