feat: add path-prefix option to convert command

Playwright and other test runners may output paths relative to their
config directory, but split patterns use repo-root paths. The path-prefix
option allows prepending a prefix to all file paths during conversion
so they match the split pattern.

Example: --path-prefix "frontends/apps/e2e/" converts "tests/foo.spec.ts"
to "frontends/apps/e2e/tests/foo.spec.ts"

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: cosmith

action.yml

@@ -32,6 +32,9 @@ inputs:
   to:
     description: 'Timing JSON file to write (for convert)'
     required: false
+  path-prefix:
+    description: 'Prefix to prepend to file paths (for convert) - use to match paths with split pattern'
+    required: false
   # merge inputs
   prefix:
     description: 'Prefix to match timing JSON files (for merge)'
@@ -101,7 +104,8 @@ runs:
       run: |
         bun run ${{ github.action_path }}/index.ts convert \
           --from "${{ inputs.from }}" \
-          --to "${{ inputs.to }}"
+          --to "${{ inputs.to }}" \
+          ${{ inputs.path-prefix != '' && format('--path-prefix "{0}"', inputs.path-prefix) || '' }}
 
     - name: Run merge
       if: inputs.command == 'merge'

bun.lockb

@@ -19,6 +19,9 @@ const { positionals, values } = parseArgs({
     to: {
       type: "string",
     },
+    ["path-prefix"]: {
+      type: "string",
+    },
     // merge options
     ["timings-file"]: {
       type: "string",
@@ -78,10 +81,13 @@ fairsplice convert
 Convert JUnit XML to timing JSON (for a single worker).
 
 Required options:
-    --from <file>       JUnit XML file to read
-    --to <file>         Timing JSON file to write
+    --from <file>           JUnit XML file to read
+    --to <file>             Timing JSON file to write
+
+Optional:
+    --path-prefix <prefix>  Prefix to prepend to all file paths (e.g., "src/tests/")
 
-Example: fairsplice convert --from junit.xml --to timing.json
+Example: fairsplice convert --from junit.xml --to timing.json --path-prefix "frontends/apps/e2e/"
 
 
 fairsplice merge
@@ -125,7 +131,7 @@ if (command === "split") {
     );
     process.exit(1);
   }
-  await convert({ from: values.from, to: values.to });
+  await convert({ from: values.from, to: values.to, pathPrefix: values["path-prefix"] });
   process.exit(0);
 } else if (command === "merge") {
   if (!values["timings-file"] || !values.prefix) {

index.ts

@@ -3,9 +3,11 @@ import { parseJunit } from "../lib/junit";
 export async function convert({
   from,
   to,
+  pathPrefix,
 }: {
   from: string;
   to: string;
+  pathPrefix?: string;
 }) {
   // check if input file exists
   const junitXmlFile = Bun.file(from);
@@ -27,10 +29,12 @@ export async function convert({
     if (testCase.file.includes("..")) {
       continue;
     }
-    if (!timingByFile[testCase.file]) {
-      timingByFile[testCase.file] = 0;
+    // Apply path prefix if provided
+    const filePath = pathPrefix ? `${pathPrefix}${testCase.file}` : testCase.file;
+    if (!timingByFile[filePath]) {
+      timingByFile[filePath] = 0;
     }
-    timingByFile[testCase.file] += testCase.time;
+    timingByFile[filePath] += testCase.time;
   }
 
   // convert to ms