fix: handle JSONC settings files when injecting proxy config

cmd/onecli/run.go

@@ -392,7 +392,7 @@ func maybeInstallGatewayHook(out *output.Writer, agentName, baseDir string) {
 	settings := make(map[string]any)
 	data, readErr := os.ReadFile(settingsPath)
 	if readErr == nil && len(data) > 0 {
-		if err := json.Unmarshal(data, &settings); err != nil {
+		if err := json.Unmarshal(stripJSONC(data), &settings); err != nil {
 			return
 		}
 	}
@@ -525,8 +525,8 @@ func mergeVSCodeProxySettings(path, proxyURL, authHeader string, terminalEnv map
 	settings := make(map[string]any)
 	data, readErr := os.ReadFile(path)
 	if readErr == nil && len(data) > 0 {
-		if err := json.Unmarshal(data, &settings); err != nil {
-			return fmt.Errorf("settings contains comments or invalid JSON; cannot merge proxy config")
+		if err := json.Unmarshal(stripJSONC(data), &settings); err != nil {
+			return fmt.Errorf("settings contains invalid JSON; cannot merge proxy config: %w", err)
 		}
 	}
 	settings["http.proxy"] = proxyURL
@@ -560,6 +560,72 @@ func mergeVSCodeProxySettings(path, proxyURL, authHeader string, terminalEnv map
 	return os.WriteFile(path, append(out, '\n'), 0o600)
 }
 
+// stripJSONC converts JSONC (JSON with Comments) to strict JSON by removing
+// single-line comments (//), block comments (/* */), and trailing commas
+// before ] or }. String contents are preserved.
+func stripJSONC(data []byte) []byte {
+	out := make([]byte, 0, len(data))
+	i := 0
+	for i < len(data) {
+		// String literal — copy verbatim, including escaped quotes.
+		if data[i] == '"' {
+			out = append(out, '"')
+			i++
+			for i < len(data) {
+				if data[i] == '\\' && i+1 < len(data) {
+					out = append(out, data[i], data[i+1])
+					i += 2
+					continue
+				}
+				out = append(out, data[i])
+				if data[i] == '"' {
+					i++
+					break
+				}
+				i++
+			}
+			continue
+		}
+		// Single-line comment.
+		if i+1 < len(data) && data[i] == '/' && data[i+1] == '/' {
+			for i < len(data) && data[i] != '\n' {
+				i++
+			}
+			continue
+		}
+		// Block comment.
+		if i+1 < len(data) && data[i] == '/' && data[i+1] == '*' {
+			i += 2
+			for i < len(data) {
+				if data[i] == '*' && i+1 < len(data) && data[i+1] == '/' {
+					i += 2
+					break
+				}
+				i++
+			}
+			continue
+		}
+		out = append(out, data[i])
+		i++
+	}
+
+	// Remove trailing commas: `,` followed by optional whitespace then `]` or `}`.
+	result := make([]byte, 0, len(out))
+	for j := 0; j < len(out); j++ {
+		if out[j] == ',' {
+			k := j + 1
+			for k < len(out) && (out[k] == ' ' || out[k] == '\t' || out[k] == '\n' || out[k] == '\r') {
+				k++
+			}
+			if k < len(out) && (out[k] == ']' || out[k] == '}') {
+				continue
+			}
+		}
+		result = append(result, out[j])
+	}
+	return result
+}
+
 func stripProxyCredentials(env []string) []string {
 	proxyKeys := map[string]bool{
 		"HTTPS_PROXY": true, "HTTP_PROXY": true,

cmd/onecli/run_test.go

@@ -252,21 +252,93 @@ func TestMergeVSCodeProxySettings_TerminalEnv(t *testing.T) {
 	}
 }
 
-func TestMergeVSCodeProxySettings_RejectsJSONC(t *testing.T) {
+func TestMergeVSCodeProxySettings_HandlesJSONC(t *testing.T) {
 	dir := t.TempDir()
 	path := filepath.Join(dir, "settings.json")
 	writeJSON(t, path, `{
     // this is a comment
-    "editor.fontSize": 14
+    "editor.fontSize": 14,
 }
 `)
 
 	err := mergeVSCodeProxySettings(path, "https://proxy:8080", "Basic dTpw", nil)
-	if err == nil {
-		t.Fatal("expected error for JSONC input")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	got := readSettingsMap(t, path)
+	if got["editor.fontSize"] != float64(14) {
+		t.Errorf("editor.fontSize = %v, want 14", got["editor.fontSize"])
+	}
+	if got["http.proxy"] != "https://proxy:8080" {
+		t.Errorf("http.proxy = %v", got["http.proxy"])
 	}
-	if !strings.Contains(err.Error(), "comments or invalid JSON") {
-		t.Errorf("error = %q, want mention of comments", err.Error())
+}
+
+func TestStripJSONC(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{
+			"strict JSON unchanged",
+			`{"key": "value", "num": 42}`,
+			`{"key": "value", "num": 42}`,
+		},
+		{
+			"single-line comments",
+			"{// comment\n\"key\": \"value\"\n}",
+			"{\n\"key\": \"value\"\n}",
+		},
+		{
+			"block comments",
+			`{"key": /* inline */ "value"}`,
+			`{"key":  "value"}`,
+		},
+		{
+			"trailing comma before }",
+			`{"a": 1, "b": 2,}`,
+			`{"a": 1, "b": 2}`,
+		},
+		{
+			"trailing comma before ]",
+			`[1, 2, 3,]`,
+			`[1, 2, 3]`,
+		},
+		{
+			"trailing comma with whitespace",
+			"{\"a\": 1,\n  }",
+			"{\"a\": 1\n  }",
+		},
+		{
+			"slashes inside strings preserved",
+			`{"url": "https://example.com"}`,
+			`{"url": "https://example.com"}`,
+		},
+		{
+			"escaped quotes in strings",
+			`{"key": "val\"ue // not a comment"}`,
+			`{"key": "val\"ue // not a comment"}`,
+		},
+		{
+			"unterminated block comment",
+			`{"a": 1} /* oops`,
+			`{"a": 1} `,
+		},
+		{
+			"combined comments and trailing commas",
+			"{\n  // editor settings\n  \"fontSize\": 14,\n  \"theme\": \"dark\", // inline\n}",
+			"{\n  \n  \"fontSize\": 14,\n  \"theme\": \"dark\" \n}",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := string(stripJSONC([]byte(tt.input)))
+			if got != tt.want {
+				t.Errorf("got  %q\nwant %q", got, tt.want)
+			}
+		})
 	}
 }