Add KiCad fork diff statistics script

- scripts/kicad-diff-stats.sh: Shows how far our KiCad fork has diverged
  from upstream (last non-our commit)
- Outputs: commit count, files changed, lines added/deleted, file list
- Logs to logs/kicad-diff/ with timestamps
- Update CLAUDE.md with script reference

Current status: 5 commits, 81 files, +1536/-395 lines on top of upstream

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CLAUDE.md

@@ -1,19 +1,22 @@
 The goal is to build kicad with wasm and run it in a browser
-The original research docs are in /docs
+
 A lot of native module have to be compiled to wasm, the most complex is wxwidgets
 /kicad and /wxwidgets are git submodules from our own forks
 The e2e tests are in /tests, with a README and WHATWORKS md files
 The e2e tests are separated per feature
-The tests depend on canvas, there's an app to find button positions, use that, don't find buttons by estimating pixels
+Wxwidgets wasm port has hooks for finding positions of UI elements, tests use that
-The test have screenshots that are tracked with git, use compare-screenshots.sh to see what changed, update them when a new image is added
+The test have screenshots that are tracked with git, use compare-screenshots.sh to see what changed
-The tests have log files after each run where the js console and cpp logs are visible
+Update test images with /scripts/update-baseline-screenshots.sh when a new image is added
+The tests have log files in tests/logs/{wxwidgets/kicad}/{test-name} after each run where the js console and cpp logs are visible
 Always check screenshots for validating tests
 
-Our current goal is to test every wxwidgets feature kicad uses, write the wasm layer and e2e tests, documented in WHATWORKS
+Build wxwidgets with scripts/build-wxuniversal-wasm.sh
-Never run builds manually, we have scripts that run the builds in the /scripts folder
+Build kicad with docker/build.sh
-Build wxwidgets and tests with scripts, not manually
+Build CPP wxwidgets tests with scripts/builds-wasm-test.sh
-Don't change the wxwidgets core unless absolutely necessary, try to fix things in the wasm layer
-Don't try to guess what's broken in wxwidgets, use debug tools / symbols, supported by the build script
 
-# Next up
+Don't change the wxwidgets core unless absolutely necessary, try to fix things in the wasm layer.
-porting kicad, with most of the dependencies shimmed out and load it in a browser
+Don't change kicad unless absolutely necessary - keep our fork as close to upstream as possible.
+Run scripts/kicad-diff-stats.sh to see how far our KiCad fork has diverged from upstream.
+It's okay to add temporary logging that will be removed for debugging.
+
+Don't try to guess what's broken , use debug tools / symbols, supported by the build scripts

scripts/kicad-diff-stats.sh

@@ -0,0 +1,174 @@
+#!/bin/bash
+# Show diff statistics between current KiCad HEAD and last upstream commit
+#
+# This helps track how far our KiCad fork has diverged from upstream.
+# We want to keep changes minimal to ease future porting.
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(dirname "$SCRIPT_DIR")"
+KICAD_DIR="$PROJECT_ROOT/kicad"
+LOGS_DIR="$PROJECT_ROOT/logs/kicad-diff"
+
+# Create logs directory
+mkdir -p "$LOGS_DIR"
+
+# Log file with timestamp
+TIMESTAMP="$(date +%Y%m%d-%H%M%S)"
+LOG_FILE="$LOGS_DIR/${TIMESTAMP}.log"
+
+# Our commit authors (add more if needed)
+OUR_AUTHORS=(
+    "viktor.vaczi@emergence-engineering.com"
+    "noreply@anthropic.com"
+)
+
+echo "=== KiCad Fork Diff Statistics ===" | tee "$LOG_FILE"
+echo "Generated: $(date)" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+
+cd "$KICAD_DIR"
+
+# Find the last commit NOT made by us
+echo "Finding last upstream commit..." | tee -a "$LOG_FILE"
+
+# Build grep pattern for our authors
+AUTHOR_PATTERN=""
+for author in "${OUR_AUTHORS[@]}"; do
+    if [ -n "$AUTHOR_PATTERN" ]; then
+        AUTHOR_PATTERN="$AUTHOR_PATTERN\|"
+    fi
+    AUTHOR_PATTERN="$AUTHOR_PATTERN$author"
+done
+
+# Find first commit that doesn't match our authors
+UPSTREAM_COMMIT=""
+while read -r commit_hash author_email; do
+    is_ours=false
+    for our_author in "${OUR_AUTHORS[@]}"; do
+        if [[ "$author_email" == "$our_author" ]]; then
+            is_ours=true
+            break
+        fi
+    done
+    if [ "$is_ours" = false ]; then
+        UPSTREAM_COMMIT="$commit_hash"
+        UPSTREAM_AUTHOR="$author_email"
+        break
+    fi
+done < <(git log --format="%H %ae" HEAD)
+
+if [ -z "$UPSTREAM_COMMIT" ]; then
+    echo "ERROR: Could not find upstream commit" | tee -a "$LOG_FILE"
+    exit 1
+fi
+
+# Get commit info
+UPSTREAM_SUBJECT=$(git log -1 --format="%s" "$UPSTREAM_COMMIT")
+UPSTREAM_DATE=$(git log -1 --format="%ci" "$UPSTREAM_COMMIT")
+
+echo "" | tee -a "$LOG_FILE"
+echo "Current HEAD: $(git rev-parse --short HEAD)" | tee -a "$LOG_FILE"
+echo "Last upstream commit: $(git rev-parse --short $UPSTREAM_COMMIT)" | tee -a "$LOG_FILE"
+echo "  Author: $UPSTREAM_AUTHOR" | tee -a "$LOG_FILE"
+echo "  Date: $UPSTREAM_DATE" | tee -a "$LOG_FILE"
+echo "  Subject: $UPSTREAM_SUBJECT" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+
+# Count our commits on top
+OUR_COMMIT_COUNT=$(git rev-list --count "$UPSTREAM_COMMIT"..HEAD)
+echo "Our commits on top of upstream: $OUR_COMMIT_COUNT" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+
+# Get diff statistics
+echo "=== Diff Statistics ===" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+
+# Overall stats
+DIFF_STAT=$(git diff --stat "$UPSTREAM_COMMIT"..HEAD)
+DIFF_SHORTSTAT=$(git diff --shortstat "$UPSTREAM_COMMIT"..HEAD)
+
+echo "Summary: $DIFF_SHORTSTAT" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+
+# Detailed breakdown
+DIFF_NUMSTAT=$(git diff --numstat "$UPSTREAM_COMMIT"..HEAD)
+
+# Count files by type
+TOTAL_FILES=0
+TOTAL_INSERTIONS=0
+TOTAL_DELETIONS=0
+MODIFIED_FILES=0
+ADDED_FILES=0
+DELETED_FILES=0
+
+while IFS=$'\t' read -r added deleted filename; do
+    # Skip empty lines
+    [ -z "$filename" ] && continue
+
+    TOTAL_FILES=$((TOTAL_FILES + 1))
+
+    # Handle binary files (shown as -)
+    if [ "$added" = "-" ]; then
+        added=0
+    fi
+    if [ "$deleted" = "-" ]; then
+        deleted=0
+    fi
+
+    TOTAL_INSERTIONS=$((TOTAL_INSERTIONS + added))
+    TOTAL_DELETIONS=$((TOTAL_DELETIONS + deleted))
+
+    # Categorize file changes
+    if [ "$added" -gt 0 ] && [ "$deleted" -eq 0 ]; then
+        # Check if file exists in upstream
+        if git cat-file -e "$UPSTREAM_COMMIT:$filename" 2>/dev/null; then
+            MODIFIED_FILES=$((MODIFIED_FILES + 1))
+        else
+            ADDED_FILES=$((ADDED_FILES + 1))
+        fi
+    elif [ "$added" -eq 0 ] && [ "$deleted" -gt 0 ]; then
+        # Check if file exists in HEAD
+        if git cat-file -e "HEAD:$filename" 2>/dev/null; then
+            MODIFIED_FILES=$((MODIFIED_FILES + 1))
+        else
+            DELETED_FILES=$((DELETED_FILES + 1))
+        fi
+    else
+        MODIFIED_FILES=$((MODIFIED_FILES + 1))
+    fi
+done <<< "$DIFF_NUMSTAT"
+
+echo "Files changed:    $TOTAL_FILES" | tee -a "$LOG_FILE"
+echo "  Added:          $ADDED_FILES" | tee -a "$LOG_FILE"
+echo "  Modified:       $MODIFIED_FILES" | tee -a "$LOG_FILE"
+echo "  Deleted:        $DELETED_FILES" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+echo "Lines changed:" | tee -a "$LOG_FILE"
+echo "  Insertions:     +$TOTAL_INSERTIONS" | tee -a "$LOG_FILE"
+echo "  Deletions:      -$TOTAL_DELETIONS" | tee -a "$LOG_FILE"
+echo "  Net change:     $((TOTAL_INSERTIONS - TOTAL_DELETIONS))" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+
+# List changed files
+echo "=== Changed Files ===" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+
+# Get list with change type
+git diff --name-status "$UPSTREAM_COMMIT"..HEAD | while IFS=$'\t' read -r status filename; do
+    case "$status" in
+        A) status_text="[ADDED]    " ;;
+        M) status_text="[MODIFIED] " ;;
+        D) status_text="[DELETED]  " ;;
+        R*) status_text="[RENAMED]  " ;;
+        C*) status_text="[COPIED]   " ;;
+        *) status_text="[$status]      " ;;
+    esac
+    echo "$status_text $filename" | tee -a "$LOG_FILE"
+done
+
+echo "" | tee -a "$LOG_FILE"
+echo "=== End of Report ===" | tee -a "$LOG_FILE"
+echo "" | tee -a "$LOG_FILE"
+echo "Full log saved to: $LOG_FILE"