Added initial npm diff.

npm/npm-diff/npm_diff.sh

@@ -0,0 +1,110 @@
+#!/bin/bash
+set -e
+
+PACKAGE_NAME="$1"
+LHS_VERSION="$2"
+RHS_VERSION="$3"
+WORKING_DIR="$4"
+REGISTRY="$5"
+DIFF_OPTIONS="$6"
+OUTPUT_FILE="$7"
+FAIL_ON_DIFF="$8"
+
+if [[ ! -f "$GITHUB_OUTPUT" ]]; then
+    GITHUB_OUTPUT="/dev/fd/1"
+fi
+
+# Change to working directory if specified
+if [[ -n "$WORKING_DIR" && "$WORKING_DIR" != "." ]]; then
+    cd "$WORKING_DIR"
+fi
+
+# Configure npm registry
+if [[ -n "$REGISTRY" && "$REGISTRY" != "https://registry.npmjs.org" ]]; then
+    npm config set registry "$REGISTRY"
+fi
+
+# Build the npm diff command
+DIFF_CMD="npm diff"
+
+# Add package specs using correct --diff syntax
+if [[ -n "$PACKAGE_NAME" ]]; then
+    if [[ -n "$LHS_VERSION" && -n "$RHS_VERSION" ]]; then
+        # Compare two specific published versions (LHS as "from", RHS as "to")
+        DIFF_CMD="$DIFF_CMD --diff=$PACKAGE_NAME@$LHS_VERSION --diff=$PACKAGE_NAME@$RHS_VERSION"
+    elif [[ -n "$LHS_VERSION" ]]; then
+        # Compare local/installed to the specified LHS version
+        DIFF_CMD="$DIFF_CMD --diff=$PACKAGE_NAME@$LHS_VERSION"
+    elif [[ -n "$RHS_VERSION" ]]; then
+        # Compare local/installed to the specified RHS version
+        DIFF_CMD="$DIFF_CMD --diff=$PACKAGE_NAME@$RHS_VERSION"
+    else
+        # Compare local/installed to the latest published version
+        DIFF_CMD="$DIFF_CMD --diff=$PACKAGE_NAME"
+    fi
+else
+    # No package name provided: compare current workspace to its latest published version
+    # (standard behavior of plain `npm diff` in a package directory)
+    :
+fi
+
+# Add any additional diff options (e.g., --diff-name-only, file paths for filtering, etc.)
+if [[ -n "$DIFF_OPTIONS" ]]; then
+    DIFF_CMD="$DIFF_CMD $DIFF_OPTIONS"
+fi
+
+echo "Running: $DIFF_CMD"
+
+# Run npm diff and capture output
+DIFF_OUTPUT=$(eval "$DIFF_CMD" 2>&1) || DIFF_EXIT_CODE=$?
+
+# npm diff returns exit code 0 if no differences, 1 if differences found
+if [[ -z "$DIFF_EXIT_CODE" ]]; then
+    DIFF_EXIT_CODE=0
+fi
+
+# Determine if differences were found
+if [[ $DIFF_EXIT_CODE -eq 0 ]]; then
+    HAS_DIFFERENCES="false"
+    echo "No differences found"
+else
+    HAS_DIFFERENCES="true"
+    echo "Differences found"
+fi
+
+# Save diff output to file if specified
+if [[ -n "$OUTPUT_FILE" ]]; then
+    echo "$DIFF_OUTPUT" > "$OUTPUT_FILE"
+    echo "Diff output saved to $OUTPUT_FILE"
+fi
+
+# Output the diff to console
+if [[ -n "$DIFF_OUTPUT" ]]; then
+    echo "========== DIFF OUTPUT =========="
+    echo "$DIFF_OUTPUT"
+    echo "================================="
+fi
+
+# Set output variables (truncate diffOutput if too large)
+echo "hasDifferences=$HAS_DIFFERENCES" >> "$GITHUB_OUTPUT"
+
+# Truncate diff output for GitHub Actions output (max ~1MB)
+TRUNCATED_OUTPUT=$(echo "$DIFF_OUTPUT" | head -c 100000)
+if [[ ${#DIFF_OUTPUT} -gt 100000 ]]; then
+    TRUNCATED_OUTPUT="$TRUNCATED_OUTPUT... (output truncated)"
+fi
+
+# Use multiline output format for GitHub Actions
+{
+    echo "diffOutput<<EOF"
+    echo "$TRUNCATED_OUTPUT"
+    echo "EOF"
+} >> "$GITHUB_OUTPUT"
+
+# Fail if differences found and failOnDifferences is true
+if [[ "$HAS_DIFFERENCES" == "true" && "$FAIL_ON_DIFF" == "true" ]]; then
+    echo "Error: Differences found and failOnDifferences is set to true"
+    exit 1
+fi
+
+exit 0