fix(codeclimate): always emit location.lines.begin for GitLab.

File-level recipe rows (e.g. boundary-violations) default begin to 1 when line_start is absent; clarify README format comment.

Author: SutuSebastian

README.md

@@ -131,9 +131,9 @@ codemap audit --base v1.0.0 --files-baseline pre-release-files  # mix --base wit
 # non-git projects get a clean `codemap audit: --base requires a git repository.` error.
 # Recipes that define per-row action templates append "actions" hints (kebab-case verb +
 # description) in --json output; ad-hoc SQL never carries actions. Inspect via --recipes-json.
-# --format <text|json|sarif|annotations|mermaid|diff|diff-json|codeclimate|badge> — pipe results into GitHub Code Scanning
-# (SARIF 2.1.0), surface findings inline on PRs (GH Actions ::notice file=…,line=…::msg), or
-# render edge-shaped recipes as Mermaid `flowchart LR`, or preview edits as unified diffs. All
+# --format <text|json|sarif|annotations|mermaid|diff|diff-json|codeclimate|badge> — SARIF for GitHub
+# Code Scanning; annotations for GH Actions ::notice lines; codeclimate for GitLab Code Quality;
+# badge for issue-count summaries; mermaid/diff for graph and edit previews. All
 # formatted outputs require a flat row list
 # (no --summary / --group-by / baseline). SARIF / annotations auto-detect file_path /
 # path / to_path / from_path; rule.id is codemap.<recipe-id> (or codemap.adhoc). Mermaid

docs/plans/ci-output-formats.md

@@ -48,7 +48,7 @@ Moat A: formatters only — no new analysis.
 | #   | Decision                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | Source                                                                                |
 | --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- |
 | F.1 | **Two new format ids** — `codeclimate` and `badge` on `codemap query` / MCP `query` / `query_recipe` (same `output-formatters.ts` home as SARIF).                                                                                                                                                                                                                                                                                                                                                                                                                                                  | [Moat A](../roadmap.md#moats-load-bearing) — output mode only                         |
-| F.2 | **Code Climate shape** — JSON array of objects: `description`, `check_name`, `fingerprint`, `location.path`, `location.lines.begin`, `severity` (`info`\|`minor`\|`major`\|`critical`\|`blocker`).                                                                                                                                                                                                                                                                                                                                                                                                 | [GitLab Code Quality format](https://docs.gitlab.com/ee/ci/testing/code_quality.html) |
+| F.2 | **Code Climate shape** — JSON array of objects: `description`, `check_name`, `fingerprint`, `location.path`, `location.lines.begin` (`line_start` when present, else `1` for file-level rows), `severity` (`info`\|`minor`\|`major`\|`critical`\|`blocker`).                                                                                                                                                                                                                                                                                                                                       | [GitLab Code Quality format](https://docs.gitlab.com/ee/ci/testing/code_quality.html) |
 | F.3 | **Fingerprint** — stable hash from `(recipe_id, file_path, line_start, check_name)` (FNV-1a or SHA-256 truncated) so GitLab dedupes across runs.                                                                                                                                                                                                                                                                                                                                                                                                                                                   | GitLab dedup semantics                                                                |
 | F.4 | **Badge count source** — row count after location filtering (same rows Code Climate would emit); no network fetch in core.                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Output formatter only                                                                 |
 | F.5 | **Location contract** — reuse `detectLocationColumn` from SARIF/annotations; skip rows without locatable columns (same stderr warning as SARIF aggregates).                                                                                                                                                                                                                                                                                                                                                                                                                                        | `output-formatters.ts`                                                                |

src/application/output-formatters.test.ts

@@ -317,13 +317,31 @@ describe("formatCodeClimate", () => {
     expect(JSON.parse(out)).toHaveLength(1);
   });
 
-  it("omits location.lines when line_start is absent", () => {
+  it("defaults location.lines.begin to 1 when line_start is absent", () => {
     const out = formatCodeClimate({
       rows: [{ file_path: "a.ts", fan_in: 17 }],
       recipeId: "fan-in",
     });
     const issues = JSON.parse(out);
-    expect(issues[0].location).toEqual({ path: "a.ts" });
+    expect(issues[0].location).toEqual({
+      path: "a.ts",
+      lines: { begin: 1 },
+    });
+  });
+
+  it("emits begin for boundary-style rows without line_start", () => {
+    const out = formatCodeClimate({
+      rows: [
+        {
+          file_path: "src/ui/App.tsx",
+          to_path: "src/server/db.ts",
+          rule_name: "ui-cant-touch-server",
+        },
+      ],
+      recipeId: "boundary-violations",
+    });
+    const issues = JSON.parse(out);
+    expect(issues[0].location.lines.begin).toBe(1);
   });
 
   it("buildCodeClimateFingerprint uses adhoc when recipeId omitted", () => {

src/application/output-formatters.ts

@@ -227,10 +227,13 @@ export function formatCodeClimate(opts: FormatOpts): string {
       typeof lineStartRaw === "number" && lineStartRaw > 0
         ? lineStartRaw
         : undefined;
-    const location: { path: string; lines?: { begin: number } } = { path };
-    if (lineStart !== undefined) {
-      location.lines = { begin: lineStart };
-    }
+    // GitLab requires location.lines.begin — file-level rows (e.g. boundary-violations)
+    // fall back to 1 when the recipe has no line_start column.
+    const begin = lineStart ?? 1;
+    const location: { path: string; lines: { begin: number } } = {
+      path,
+      lines: { begin },
+    };
     return [
       {
         description: buildMessageText(row),