fix(shared): hydrate PATH with Nushell login shells

packages/shared/src/shell.test.ts

@@ -122,6 +122,26 @@ describe("readPathFromLaunchctl", () => {
 });
 
 describe("readEnvironmentFromLoginShell", () => {
+  it("uses Nushell-compatible syntax for a nu login shell", () => {
+    const execFile = vi.fn<
+      (
+        file: string,
+        args: ReadonlyArray<string>,
+        options: { encoding: "utf8"; timeout: number },
+      ) => string
+    >(() => "__T3CODE_ENV_PATH_START__\n/a:/b\n__T3CODE_ENV_PATH_END__\n");
+
+    expect(readEnvironmentFromLoginShell("/opt/homebrew/bin/nu", ["PATH"], execFile)).toEqual({
+      PATH: "/a:/b",
+    });
+
+    const command = execFile.mock.calls[0]?.[1][1];
+    expect(command).toBe(
+      "print '__T3CODE_ENV_PATH_START__'; try { printenv PATH } catch { print '' }; print '__T3CODE_ENV_PATH_END__'",
+    );
+    expect(command).not.toContain("|| true");
+  });
+
   it("extracts multiple environment variables from a login shell command", () => {
     const execFile = vi.fn<
       (

packages/shared/src/shell.ts

@@ -245,13 +245,28 @@ function envCaptureEnd(name: string): string {
   return `__T3CODE_ENV_${name}_END__`;
 }
 
-function buildEnvironmentCaptureCommand(names: ReadonlyArray<string>): string {
+function isNushellExecutable(shell: string): boolean {
+  const executableName = NodePath.basename(shell).toLowerCase();
+  return executableName === "nu" || executableName === "nu.exe";
+}
+
+function buildEnvironmentCaptureCommand(shell: string, names: ReadonlyArray<string>): string {
+  const isNushell = isNushellExecutable(shell);
+
   return names
     .map((name) => {
       if (!SHELL_ENV_NAME_PATTERN.test(name)) {
         throw new Error(`Unsupported environment variable name: ${name}`);
       }
 
+      if (isNushell) {
+        return [
+          `print '${envCaptureStart(name)}'`,
+          `try { printenv ${name} } catch { print '' }`,
+          `print '${envCaptureEnd(name)}'`,
+        ].join("; ");
+      }
+
       return [
         `printf '%s\\n' '${envCaptureStart(name)}'`,
         `printenv ${name} || true`,
@@ -312,7 +327,7 @@ export const readEnvironmentFromLoginShell: ShellEnvironmentReader = (
     return {};
   }
 
-  const output = execFile(shell, ["-ilc", buildEnvironmentCaptureCommand(names)], {
+  const output = execFile(shell, ["-ilc", buildEnvironmentCaptureCommand(shell, names)], {
     encoding: "utf8",
     timeout: 5000,
   });