fix(render): avoid implicit baseline and artifact claims

.github/workflows/ci.yml

@@ -145,16 +145,22 @@ jobs:
             echo
             cat coverage-pr-build.md
           } > coverage-pr-comment.md
-      - name: Publish run summary
-        run: cat coverage-pr-comment.md >> "$GITHUB_STEP_SUMMARY"
       - name: Upload PR-build coverage
+        id: coverage-artifact
         uses: actions/upload-artifact@v7
         with:
           name: coverage-pr-build
           if-no-files-found: error
           path: |
             coverage-pr-head.lcov
             coverage-pr-comment.md
+      # The archived report has the run link; the upload URL exists only after upload.
+      - name: Link PR-build artifact and publish run summary
+        env:
+          ARTIFACT_URL: ${{ steps.coverage-artifact.outputs.artifact-url }}
+        run: |
+          printf '\n<sub>📦 [PR-build coverage report (LCOV and Markdown)](%s)</sub>\n' "$ARTIFACT_URL" >> coverage-pr-comment.md
+          cat coverage-pr-comment.md >> "$GITHUB_STEP_SUMMARY"
       - name: Comment PR-build coverage
         if: github.event.pull_request.head.repo.fork != true
         uses: marocchino/sticky-pull-request-comment@v3

CONTRIBUTING.md

@@ -116,6 +116,9 @@ PR head, builds its debug `patchcov` binary with the lockfile, then measures tha
 checkout with cargo-llvm-cov. The local binary renders a separate sticky comment and
 enforces 90% patch coverage and 95% overall line coverage. Its report is also in the
 run summary and the `coverage-pr-build` artifact, including when a coverage gate fails.
+The posted comment and run summary link directly to that artifact, labeled as LCOV and
+Markdown. The archived comment includes the run link; the direct artifact link is added
+after upload, when its URL is available.
 Fork PRs skip the comment and still get the summary, artifact and gates. This job is not
 in the ruleset or required-check list and is skipped on pushes and merge groups.
 

README.md

@@ -55,10 +55,9 @@ report so the per-file table appears:
 >
 > </details>
 >
-> <sub>Full per-file summary is attached as the **coverage-summary** build artifact.</sub>
 
 Without `--baseline-report` there is no delta on the `Total` line, no per-file table and no
-indirect changes; a "No baseline available yet" notice stands in for them and the patch
+indirect changes; a "No baseline report supplied" notice stands in for them and the patch
 section is unchanged. With `-o json` or `-o yaml` the same result is structured
 data, in the shape described in the [output schema](docs/reference.md#output-schema):
 

docs/reference.md

@@ -60,10 +60,16 @@ use the repository working directory.
 | `--ignore-filename-regex <REGEX>` | Exclude matching files from both reports (repeatable or comma-separated); unioned with `diff.ignore-filename-regex` |
 | `--config-dir <PATH>` | Directory searched for `config.yaml` (default: the discovered `.patchcov/`, honouring `PATCHCOV_CONFIG_DIR`) |
 | `--artifact-url <URL>` | Link to the full coverage-summary artifact, in the markdown footer |
-| `--run-url <URL>` | Link to the CI run, in the markdown footer |
+| `--run-url <URL>` | Link to the CI run, in the markdown footer, independently of `--artifact-url` |
 | `--commit-url <URL>` | Commit-URL prefix for linking SHAs |
 | `--base-sha <SHA>` / `--head-sha <SHA>` | SHAs shown in the markdown `Comparing` line (both are needed for the line to appear) |
 
+Markdown reports omit artifact guidance when no nonempty artifact URL is supplied. An explicit
+`--artifact-url` (or `COVERAGE_ARTIFACT_URL`) is labeled as a full per-file coverage summary;
+only use it for an artifact containing that summary. A run URL renders even without an
+artifact URL. Without `--baseline-report`, per-file deltas and indirect coverage changes
+are unavailable; the report makes no assumptions about CI baseline publication.
+
 For both `--fail-under-*` flags, space-separated negative float values such as `-inf`,
 `-nan` and `-.5` receive the same explanatory usage error as the `--flag=value` spelling.
 A following option instead of a value reports `a value is required`.

src/render.rs

@@ -60,7 +60,7 @@ pub struct RenderOptions {
     pub no_explanation: bool,
     /// Link to the full coverage-summary artifact.
     pub artifact_url: Option<String>,
-    /// Link to the CI run.
+    /// Link to the CI run, rendered independently of the artifact URL.
     pub run_url: Option<String>,
     /// Base (merge-base) commit SHA.
     pub base_sha: Option<String>,
@@ -249,9 +249,8 @@ fn render_markdown(diff: &CoverageDiff, opts: &RenderOptions) -> String {
         render_notable_unchanged(diff, &mut out);
     } else {
         out.push_str(
-            "_No baseline available yet (first run, or the `main` baseline artifact was \
-             missing). Per-file deltas will appear on PRs once a baseline has been published \
-             from `main`._\n\n",
+            "_No baseline report supplied. Per-file deltas and indirect coverage changes \
+             require a baseline report._\n\n",
         );
     }
     // Also without a baseline: `ignore` still shapes the total and the patch.
@@ -542,23 +541,22 @@ fn render_indirect_section(diff: &CoverageDiff, out: &mut String) {
 }
 
 fn render_footer(opts: &RenderOptions, out: &mut String) {
-    match opts.artifact_url.as_deref().filter(|u| !u.is_empty()) {
-        Some(artifact) => {
-            out.push_str(&format!(
-                "<sub>📦 [Full per-file coverage summary]({artifact})"
-            ));
-            if let Some(run) = opts.run_url.as_deref().filter(|u| !u.is_empty()) {
-                out.push_str(&format!(" · [run summary]({run})"));
-            }
-            out.push_str("</sub>\n");
-        }
-        None => {
-            out.push_str(
-                "<sub>Full per-file summary is attached as the **coverage-summary** build \
-                 artifact.</sub>\n",
-            );
+    let artifact = opts.artifact_url.as_deref().filter(|u| !u.is_empty());
+    let run = opts.run_url.as_deref().filter(|u| !u.is_empty());
+    if artifact.is_none() && run.is_none() {
+        return;
+    }
+    out.push_str("<sub>");
+    if let Some(artifact) = artifact {
+        out.push_str(&format!("📦 [Full per-file coverage summary]({artifact})"));
+    }
+    if let Some(run) = run {
+        if artifact.is_some() {
+            out.push_str(" · ");
         }
+        out.push_str(&format!("[run summary]({run})"));
     }
+    out.push_str("</sub>\n");
 }
 
 // ---------------------------------------------------------------------------
@@ -937,7 +935,11 @@ mod tests {
         assert!(md.contains("### Patch coverage"));
         assert!(md.contains("Patch: **80%** (4/5 new lines covered)"));
         assert!(md.contains("`src/a.rs:9`"));
-        assert!(md.contains("No baseline available yet"));
+        assert!(md.contains("No baseline report supplied"));
+        assert!(md.contains("require a baseline report"));
+        assert!(!md.contains("will appear"));
+        assert!(!md.contains("baseline artifact"));
+        assert!(!md.contains("`main`"));
     }
 
     #[test]
@@ -1390,6 +1392,32 @@ mod tests {
         assert!(md.contains("[run summary](https://run)"));
     }
 
+    #[test]
+    fn markdown_footer_links_are_independent_and_optional() {
+        for artifact in [None, Some(""), Some("https://artifact")] {
+            for run in [None, Some(""), Some("https://run")] {
+                let opts = RenderOptions {
+                    artifact_url: artifact.map(str::to_string),
+                    run_url: run.map(str::to_string),
+                    ..Default::default()
+                };
+                let md = render(&sample_diff(), &opts, OutputFormat::Markdown).unwrap();
+                let has_artifact = artifact == Some("https://artifact");
+                let has_run = run == Some("https://run");
+                assert_eq!(
+                    md.contains("[Full per-file coverage summary](https://artifact)"),
+                    has_artifact,
+                    "{md}"
+                );
+                assert_eq!(md.contains("[run summary](https://run)"), has_run, "{md}");
+                assert_eq!(md.contains("<sub>"), has_artifact || has_run, "{md}");
+                assert_eq!(md.contains(" · "), has_artifact && has_run, "{md}");
+                assert!(!md.contains("coverage-summary"), "{md}");
+                assert!(!md.contains("attached"), "{md}");
+            }
+        }
+    }
+
     #[test]
     fn markdown_comparing_line_and_covered_indirect() {
         let mut diff = sample_diff();