TUI: coalesce multiline paste submits on macOS terminals

src/tui/tui.submit-handler.test.ts

@@ -130,10 +130,32 @@ describe("shouldEnableWindowsGitBashPasteFallback", () => {
     ).toBe(true);
   });
 
-  it("disables fallback outside Windows", () => {
+  it("enables fallback on macOS iTerm", () => {
     expect(
       shouldEnableWindowsGitBashPasteFallback({
         platform: "darwin",
+        env: {
+          TERM_PROGRAM: "iTerm.app",
+        } as NodeJS.ProcessEnv,
+      }),
+    ).toBe(true);
+  });
+
+  it("enables fallback on macOS Terminal.app", () => {
+    expect(
+      shouldEnableWindowsGitBashPasteFallback({
+        platform: "darwin",
+        env: {
+          TERM_PROGRAM: "Apple_Terminal",
+        } as NodeJS.ProcessEnv,
+      }),
+    ).toBe(true);
+  });
+
+  it("disables fallback outside Windows", () => {
+    expect(
+      shouldEnableWindowsGitBashPasteFallback({
+        platform: "linux",
         env: {
           MSYSTEM: "MINGW64",
         } as NodeJS.ProcessEnv,

src/tui/tui.ts

@@ -84,13 +84,24 @@ export function shouldEnableWindowsGitBashPasteFallback(params?: {
   env?: NodeJS.ProcessEnv;
 }): boolean {
   const platform = params?.platform ?? process.platform;
+  const env = params?.env ?? process.env;
+  const termProgram = (env.TERM_PROGRAM ?? "").toLowerCase();
+
+  // Some macOS terminals emit multiline paste as rapid single-line submits.
+  // Enable burst coalescing so pasted blocks stay as one user message.
+  if (platform === "darwin") {
+    if (termProgram.includes("iterm") || termProgram.includes("apple_terminal")) {
+      return true;
+    }
+    return false;
+  }
+
   if (platform !== "win32") {
     return false;
   }
-  const env = params?.env ?? process.env;
+
   const msystem = (env.MSYSTEM ?? "").toUpperCase();
   const shell = env.SHELL ?? "";
-  const termProgram = (env.TERM_PROGRAM ?? "").toLowerCase();
   if (msystem.startsWith("MINGW") || msystem.startsWith("MSYS")) {
     return true;
   }