ENH: Add generate-lcov-html flag

spin/cmds/meson.py

@@ -1,5 +1,6 @@
 import contextlib
 import copy
+import itertools
 import json
 import os
 import re
@@ -14,6 +15,8 @@
 from .util import get_commands, get_config
 from .util import run as _run
 
+LCOV_OUTPUT_FILE = Path("build", "meson-logs", "coveragereport")
+
 
 class GcovReportFormat(str, Enum):
     html = "html"
@@ -231,6 +234,48 @@ def _check_coverage_tool_installation(coverage_type: GcovReportFormat, build_dir
         )
 
 
+def _get_coverage_files():
+    cwd = Path.cwd()
+    build_dir = Path(cwd, "build")
+    return itertools.chain(build_dir.rglob("*.gcda"), build_dir.rglob("*.da"))
+
+
+def _gcov_reset_counters():
+    click.secho("Removing previous GCOV .gcda files...", fg="yellow")
+    for filename in _get_coverage_files():
+        Path.unlink(filename)
+
+
+def _generate_lcov_coverage_html():
+    if next(_get_coverage_files(), None) is None:
+        raise click.ClickException(
+            "GCOV files missing... Cannot generate coverage reports. "
+            "Coverage reports can be generated by `spin test --coverage --gcov`"
+        )
+
+    click.secho(
+        "Deleting old HTML coverage report...",
+        fg="yellow",
+    )
+    shutil.rmtree(LCOV_OUTPUT_FILE, ignore_errors=True)
+
+    click.secho(
+        "Generating HTML coverage report...",
+        fg="blue",
+    )
+    cmd = ["ninja", "coverage-html", "-C", "build"]
+    p = _run(
+        cmd,
+        echo=True,
+        output=False,
+    )
+    coverage_folder = re.search(r"file://(.*)", p.stdout.decode("utf-8")).group(1)
+    click.secho(
+        f"Coverage report generated successfully and written to {coverage_folder}",
+        fg="green",
+    )
+
+
 if sys.platform.startswith("win"):
     DEFAULT_PREFIX = "C:/"
 else:
@@ -447,6 +492,13 @@ def _get_configured_command(command_name):
     default="html",
     help=f"Format of the gcov report. Can be one of {', '.join(e.value for e in GcovReportFormat)}.",
 )
+@click.option(
+    "--generate-lcov-html",
+    is_flag=True,
+    help="produce HTML for C code coverage information "
+    "from a previous run with --gcov. "
+    "HTML output goes to `build/meson-logs/coveragereport/`",
+)
 @build_dir_option
 @click.pass_context
 def test(
@@ -459,6 +511,7 @@ def test(
     coverage=False,
     gcov=None,
     gcov_format=None,
+    generate_lcov_html=None,
     build_dir=None,
 ):
     """🔧 Run tests
@@ -503,6 +556,10 @@ def test(
     distname = cfg.get("project.name", None)
     pytest_args = pytest_args or ()
 
+    if generate_lcov_html:
+        _generate_lcov_coverage_html()
+        sys.exit(0)
+
     # User specified tests without -t flag
     # Rewrite arguments as though they specified using -t and proceed
     if (len(pytest_args) == 1) and (not tests):
@@ -547,6 +604,7 @@ def test(
             "Invoking `build` prior to running tests:", bold=True, fg="bright_green"
         )
         if gcov is not None:
+            _gcov_reset_counters()
             ctx.invoke(build_cmd, build_dir=build_dir, gcov=bool(gcov))
         else:
             ctx.invoke(build_cmd, build_dir=build_dir)