💬 ChatGPT + Xcode Build Error Visibility Workflow

xcode-chatgpt-build-error-exposure.txt

🚨 **The Problem**  
ChatGPT Desktop can read your Xcode editor windows — but not your build errors. If you want ChatGPT to help debug compiler issues, you need to expose them in a visible file.

✅ **The Solution**  
Expose compiler issues automatically to ChatGPT by:
	1.	Watch for .xcactivitylog updates in Xcode’s DerivedData
	2.	Parse compiler errors using xclogparser
	3.	Write results to a Markdown file in your project directory
	4.	Open that file in Xcode — ChatGPT can now see it

Once the file BuildIssues.md is open in Xcode (add it to Xcode as a reference so you can keep getting realtime updates on it, do not copy it) ChatGPT can access it — just like any other visible window.

---

🛠️ **Setup Instructions**

### 1a. Install `xclogparser`
Open your 💻terminal and run:
    brew install xclogparser

### 1b. Install `fswatcher`
    brew install fswatcher

### 2. make a directory `buildtools` a level above the xcode projects root level, add the following (code for these is posted at the end of this doc):
    capture-xcode-errors.sh
    start-log-watcher.command

### 3. Put the following as a run script under your xcode target's build phases tab:
"$PROJECT_DIR/../buildtools/start-log-watcher.command" || true

### 4. Every time you build in xcode, your BuildIssues.md file will update as soon as your derived data xcactivitylog updates reflecting any errors or warnings. Be sure to include that build issues file (as a reference, do not copy). Open this file in one of xcode's editor windows. At this point, ChatGPT Desktop can see it and support you resolving the errors and warnings at your direction. 


===== SCRIPTS =====

### capture-xcode-errors.sh
#!/bin/bash

DEST_DIR="$(cd "$(dirname "$0")"/.. && pwd)"

DEBUG_LOG="$HOME/Desktop/xcode_build_issues_debug.log"
exec >> "$DEBUG_LOG" 2>&1

echo "⏰ Triggered at $(date)"

echo "# Running Xcode Build Issues Parser"
echo "Started at: $(date)"
echo "Writing to: $DEST_DIR"

XCLOGPARSER="/opt/homebrew/bin/xclogparser"
OUTPUT_FILE="$DEST_DIR/BuildIssues.md"
TMP_FILE="${OUTPUT_FILE}.tmp"

LOG_FILE=$(find ~/Library/Developer/Xcode/DerivedData -type f -name "*.xcactivitylog" -print0 | xargs -0 ls -t | head -n 1)

if [ ! -f "$LOG_FILE" ]; then
  echo "_⚠️ No build log found._" > "$TMP_FILE"
else
  INITIAL_MOD=$(stat -f "%m" "$LOG_FILE")
  for i in {1..20}; do
    sleep 0.3
    CURRENT_MOD=$(stat -f "%m" "$LOG_FILE")
    if [[ "$CURRENT_MOD" -ne "$INITIAL_MOD" ]]; then
      echo "✅ Log file updated, proceeding..."
      break
    fi
  done

  echo "# Xcode Build Issues" > "$TMP_FILE"
  echo "_Generated at $(date)_" >> "$TMP_FILE"
  echo "" >> "$TMP_FILE"

  PARSED_OUTPUT=$("$XCLOGPARSER" parse --file "$LOG_FILE" --reporter issues)
  if [[ "$PARSED_OUTPUT" == *'"errors" : [ ]'* && "$PARSED_OUTPUT" == *'"warnings" : [ ]'* ]]; then
    echo "_✅ Build succeeded — no issues found._" >> "$TMP_FILE"
  else
    echo "$PARSED_OUTPUT" >> "$TMP_FILE"
  fi
fi

mv "$TMP_FILE" "$OUTPUT_FILE"
touch "$OUTPUT_FILE"
echo "📄 Build issues written to $OUTPUT_FILE"



### =========================
### start-log-watcher.command
#!/bin/bash

export PATH="/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin"

WATCH_PATH=$(find ~/Library/Developer/Xcode/DerivedData -type f -name "*.xcactivitylog" | head -n 1 | xargs dirname)
WATCHER_SCRIPT_PATH="$(cd "$(dirname "$0")" && pwd)/capture-xcode-errors.sh"

if [ -z "$WATCH_PATH" ]; then
  echo "⚠️ No xcactivitylog path found."
  exit 0
fi

if pgrep -f "$WATCH_PATH" | grep fswatch >/dev/null; then
  echo "🔁 Watcher already running."
  exit 0
fi

# Detach watcher from shell and background it
( nohup fswatch -0 "$WATCH_PATH" | xargs -0 -n1 "$WATCHER_SCRIPT_PATH" >/dev/null 2>&1 & ) &
disown
echo "✅ Watcher launched and detached."