[FIX] Resolve unbound variable error in macOS script

[dev-yashmathur]

Summary

• What bug or feature is addressed: Resolves an unbound variable error (LANGUAGE) when launching the Gradio UI on macOS.
• Why this change is needed: The start_gradio_ui_macos.sh script enforces set -u. If the LANGUAGE environment variable is not set, evaluating "$LANGUAGE" causes a crash, preventing the UI from starting. Using ${LANGUAGE:-} safely handles the unset state.

Scope

• Files changed: start_gradio_ui_macos.sh
• What is explicitly out of scope: Any logic changes or modifications to non-macOS scripts.

Risk and Compatibility

• Target platform / path: macOS (Apple Silicon).
• Confirmation that non-target paths are unchanged: Confirmed. This script only affects the macOS Gradio launch process.

Regression Checks

• Checks run (manual and/or automated): Locally verified the script successfully completes the environment check and proceeds to launch the MLX backend server when LANGUAGE is undefined.
• Key scenarios validated: Successful UI startup without a pre-defined $LANGUAGE environment variable.

Reviewer Notes

• Known pre-existing issues not addressed: None.
• Follow-up items (if any): None.

Summary by CodeRabbit

• Bug Fixes
  • Fixed language configuration handling to safely manage unset or empty language preferences, ensuring the application defaults to English when no language setting is specified.

[coderabbitai]

📝 Walkthrough

Walkthrough

A single-line bug fix in a shell script that updates parameter expansion syntax in a case statement from $LANGUAGE to ${LANGUAGE:-} to properly handle unset or empty language variable values during control flow.

Changes

Cohort / File(s)	Summary
Shell Script Parameter Handling Fix start_gradio_ui_macos.sh	Updated case statement condition to use safe parameter expansion (${LANGUAGE:-}) instead of direct variable reference, ensuring unset/empty LANGUAGE values are handled correctly and flow to default assignment logic.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Poem

🐰 A rabbit hops through scripts so tight,
Where empty LANGUAGE caused a plight,
With ${LANGUAGE:-} in place,
The case flows just right,
Now shells handle silence with delight! ✨

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and specifically summarizes the main change: fixing an unbound variable error in a macOS script, which directly matches the changeset.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

start_gradio_ui_macos.sh (1)

92-97: ⚠️ Potential issue | 🟡 Minor

LGTM! Correct fix for unbound variable under set -u.

The ${LANGUAGE:-} expansion safely handles the case when LANGUAGE is unset, allowing the case statement to match the * pattern and fall through to the default assignment on line 97.

Cross-file advisory: Five other shell scripts have the same vulnerable pattern with case "$LANGUAGE" and set -euo pipefail enabled:

• start_gradio_ui.sh (line 83)
• start_gradio_ui_manual.sh (line 204)
• start_gradio_ui_rocm.sh (line 97)
• start_gradio_ui_macos_manual.sh (line 213)
• start_gradio_ui_rocm_manual.sh (line 218)

Consider applying this fix across all variants to prevent the same issue.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@start_gradio_ui_macos.sh` around lines 92 - 97, The case statement risks
unbound variable errors under set -u because it used LANGUAGE directly; update
each affected script to use the safe expansion "${LANGUAGE:-}" in the case
(i.e., change case "$LANGUAGE" to case "${LANGUAGE:-}") and keep the subsequent
default assignment : "${LANGUAGE:=en}"; apply the same change wherever LANGUAGE
is referenced in a case pattern across the other start_gradio_ui* scripts so the
scripts safely handle unset LANGUAGE under set -u.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Outside diff comments:
In `@start_gradio_ui_macos.sh`:
- Around line 92-97: The case statement risks unbound variable errors under set
-u because it used LANGUAGE directly; update each affected script to use the
safe expansion "${LANGUAGE:-}" in the case (i.e., change case "$LANGUAGE" to
case "${LANGUAGE:-}") and keep the subsequent default assignment :
"${LANGUAGE:=en}"; apply the same change wherever LANGUAGE is referenced in a
case pattern across the other start_gradio_ui* scripts so the scripts safely
handle unset LANGUAGE under set -u.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: d2d4f46a-4524-4ed2-8815-7722026ae35e

📥 Commits

Reviewing files that changed from the base of the PR and between 00f514a and 9e7a726.

📒 Files selected for processing (1)

• start_gradio_ui_macos.sh