Don't overwrite existing git params (#258)

Author: jmsanders

internal/cli/service_resolvecliparams.go

@@ -63,7 +63,18 @@ func resolveCliParams(yamlContent string) (string, []string, error) {
 	}
 
 	if doc.hasPath("$.on.cli.init") {
-		err = doc.MergeAtPath("$.on.cli.init", gitParamsMap)
+		// Don't overwrite existing git params
+		existingCliInit, initErr := doc.getNodeAtPath("$.on.cli.init")
+		if initErr == nil {
+			if mappingNode, ok := existingCliInit.(*ast.MappingNode); ok {
+				for _, v := range mappingNode.Values {
+					delete(gitParamsMap, v.Key.String())
+				}
+			}
+		}
+		if len(gitParamsMap) > 0 {
+			err = doc.MergeAtPath("$.on.cli.init", gitParamsMap)
+		}
 	} else {
 		err = doc.MergeAtPath("$.on", map[string]any{
 			"cli": map[string]any{

internal/cli/service_resolvecliparams_test.go

@@ -427,6 +427,37 @@ tasks:
 		require.False(t, result.Rewritten)
 	})
 
+	t.Run("does not overwrite existing CLI init param with hardcoded value", func(t *testing.T) {
+		tmpFile, err := os.CreateTemp(t.TempDir(), "test-*.yml")
+		require.NoError(t, err)
+		defer tmpFile.Close()
+
+		content := `
+on:
+  github:
+    push:
+      init:
+        commit-sha: ${{ event.git.sha }}
+  cli:
+    init:
+      commit-sha: HEAD
+
+tasks:
+  - key: "test"
+    run: echo 'hello world'
+`
+		_, err = tmpFile.WriteString(content)
+		require.NoError(t, err)
+
+		result, err := ResolveCliParamsForFile(tmpFile.Name())
+		require.NoError(t, err)
+		require.False(t, result.Rewritten)
+
+		fileContent, err := os.ReadFile(tmpFile.Name())
+		require.NoError(t, err)
+		require.Contains(t, string(fileContent), "commit-sha: HEAD")
+	})
+
 	t.Run("errors when multiple events use different param names for event.git.sha", func(t *testing.T) {
 		tmpFile, err := os.CreateTemp(t.TempDir(), "test-*.yml")
 		require.NoError(t, err)