fix: use portable arithmetic in validate-mermaid.sh

Replace ((var++)) with var=$((var + 1)) to avoid exit code 1
when incrementing from 0 with set -e enabled.

Author: jeremyeder

scripts/validate-mermaid.sh

@@ -1,24 +1,19 @@
 #!/bin/bash
-# Validate Mermaid diagrams in markdown files and standalone .mmd files
-# Extracts inline ```mermaid blocks and validates with mermaid-cli (mmdc)
-
 set -e
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 REPO_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
 TEMP_DIR=$(mktemp -d)
 trap "rm -rf $TEMP_DIR" EXIT
 
-# Colors for output
 RED='\033[0;31m'
 GREEN='\033[0;32m'
 YELLOW='\033[1;33m'
-NC='\033[0m' # No Color
+NC='\033[0m'
 
 echo "Validating Mermaid diagrams..."
 echo ""
 
-# Check if mmdc is installed
 if ! command -v mmdc &> /dev/null; then
     echo -e "${YELLOW}Warning: mermaid-cli (mmdc) is not installed${NC}"
     echo "Install with: npm install -g @mermaid-js/mermaid-cli"
@@ -32,7 +27,6 @@ fi
 ERRORS=0
 TOTAL=0
 
-# Function to extract and validate mermaid blocks from a file
 validate_markdown_file() {
     local file="$1"
     local block_num=0
@@ -42,7 +36,7 @@ validate_markdown_file() {
     local block_start_line=0
 
     while IFS= read -r line || [[ -n "$line" ]]; do
-        ((line_num++))
+        line_num=$((line_num + 1))
 
         if [[ "$line" =~ ^\`\`\`mermaid ]]; then
             in_mermaid=true
@@ -54,33 +48,27 @@ validate_markdown_file() {
         if [[ "$in_mermaid" == true ]]; then
             if [[ "$line" =~ ^\`\`\` ]]; then
                 in_mermaid=false
-                ((block_num++))
-                ((TOTAL++))
+                block_num=$((block_num + 1))
+                TOTAL=$((TOTAL + 1))
 
-                # Write to temp file and validate
                 local temp_file="$TEMP_DIR/diagram_${block_num}.mmd"
                 echo "$mermaid_content" > "$temp_file"
 
                 if [[ "$MMDC_AVAILABLE" == true ]]; then
-                    # Use mmdc for full validation
                     if mmdc -i "$temp_file" -o "$TEMP_DIR/output.svg" 2>"$TEMP_DIR/error.log"; then
                         echo -e "${GREEN}✓${NC} $file:$block_start_line (block $block_num)"
                     else
                         echo -e "${RED}✗${NC} $file:$block_start_line (block $block_num)"
-                        echo "  Error: $(cat "$TEMP_DIR/error.log" | head -3)"
-                        ((ERRORS++))
+                        echo "  Error: $(head -3 "$TEMP_DIR/error.log")"
+                        ERRORS=$((ERRORS + 1))
                     fi
                 else
-                    # Basic syntax validation without mmdc
-                    # Check for common syntax issues
                     local has_error=false
-                    
-                    # Check if diagram type is specified
                     if ! echo "$mermaid_content" | head -1 | grep -qE '^[[:space:]]*(flowchart|sequenceDiagram|classDiagram|stateDiagram|erDiagram|gantt|pie|gitGraph|journey|mindmap|timeline|quadrantChart|sankey|xychart|block)'; then
                         echo -e "${RED}✗${NC} $file:$block_start_line (block $block_num)"
                         echo "  Error: No valid diagram type found on first line"
                         has_error=true
-                        ((ERRORS++))
+                        ERRORS=$((ERRORS + 1))
                     fi
 
                     if [[ "$has_error" == false ]]; then
@@ -94,22 +82,21 @@ validate_markdown_file() {
     done < "$file"
 }
 
-# Find and validate standalone .mmd files
 echo "=== Standalone .mmd files ==="
 MMD_FILES=$(find "$REPO_ROOT" -name "*.mmd" -not -path "*/node_modules/*" -not -path "*/.git/*" 2>/dev/null || true)
 
 if [ -z "$MMD_FILES" ]; then
     echo "No standalone .mmd files found"
 else
     for file in $MMD_FILES; do
-        ((TOTAL++))
+        TOTAL=$((TOTAL + 1))
         if [[ "$MMDC_AVAILABLE" == true ]]; then
             if mmdc -i "$file" -o "$TEMP_DIR/output.svg" 2>"$TEMP_DIR/error.log"; then
                 echo -e "${GREEN}✓${NC} $file"
             else
                 echo -e "${RED}✗${NC} $file"
-                echo "  Error: $(cat "$TEMP_DIR/error.log" | head -3)"
-                ((ERRORS++))
+                echo "  Error: $(head -3 "$TEMP_DIR/error.log")"
+                ERRORS=$((ERRORS + 1))
             fi
         else
             echo -e "${YELLOW}?${NC} $file - skipped (mmdc not available)"
@@ -120,14 +107,12 @@ fi
 echo ""
 echo "=== Inline mermaid blocks in markdown ==="
 
-# Find all markdown files and extract mermaid blocks
 MD_FILES=$(find "$REPO_ROOT" -name "*.md" -not -path "*/node_modules/*" -not -path "*/.git/*" 2>/dev/null || true)
 
 if [ -z "$MD_FILES" ]; then
     echo "No markdown files found"
 else
     for file in $MD_FILES; do
-        # Check if file contains mermaid blocks
         if grep -q '```mermaid' "$file" 2>/dev/null; then
             validate_markdown_file "$file"
         fi