lvt-validate-templates

name: lvt-validate-templates description: Validate LiveTemplate template files - check syntax, parse errors, execution issues, and common problems category: core version: 1.0.0 keywords: ["lvt", "livetemplate", "lt"]

lvt:validate-templates

Validates LiveTemplate template files (*.tmpl) for syntax errors, parsing issues, execution problems, and common mistakes. Uses both html/template and LiveTemplate parsers to ensure templates work correctly.

🎯 ACTIVATION RULES

Context Detection

This skill typically runs in existing LiveTemplate projects (.lvtrc exists).

✅ Context Established By:

1. Project context - .lvtrc exists (most common scenario)
2. Agent context - User is working with lvt-assistant agent
3. Keyword context - User mentions "lvt", "livetemplate", or "lt"

Keyword matching (case-insensitive): lvt, livetemplate, lt

Trigger Patterns

With Context: ✅ Generic prompts related to this skill's purpose

Without Context (needs keywords): ✅ Must mention "lvt", "livetemplate", or "lt" ❌ Generic requests without keywords

User Prompts

When to use:

• "Validate my template file"
• "Check if my template has errors"
• "Parse this template"
• "Is my template syntax correct?"
• "Debug template errors"

Examples:

• "Validate app/posts/posts.tmpl"
• "Check the dashboard template for errors"
• "Parse my custom template"
• "Why isn't my template working?"

Quick Reference

# Validate a template file
lvt parse <template-file>

# Examples
lvt parse app/posts/posts.tmpl
lvt parse app/home/home.tmpl
lvt parse custom/template.tmpl

What It Checks

1. html/template parsing:

• Basic Go template syntax
• Properly closed tags
• Valid actions ({{...}})
• No syntax errors

2. LiveTemplate parsing:

• LiveTemplate-specific features
• WebSocket actions
• Component references
• Framework helpers

3. Template execution:

• Can execute with sample data
• No runtime errors
• Generates valid HTML

4. Common issues:

• Unclosed tags
• Mismatched {{...}} pairs
• Invalid function calls
• Missing required fields
• Suspicious patterns

Example Output

Successful validation:

Parsing template: app/posts/posts.tmpl
Template name: posts
============================================================

1. Testing html/template parsing...
   ✅ Successfully parsed with html/template

2. Defined templates:
   - posts
   - posts_table
   - posts_form

3. Testing LiveTemplate parsing...
   ✅ Successfully parsed with LiveTemplate

4. Testing template execution...
   ✅ Successfully executed (generated 2847 bytes of HTML)

5. Checking for common issues...
   ✅ No issues found

============================================================
✅ Template is valid!

Failed validation:

Parsing template: app/broken/broken.tmpl
Template name: broken
============================================================

1. Testing html/template parsing...
   ❌ Parse error: template: broken:15: unexpected "}" in operand

============================================================
❌ Template validation failed

Checklist

• Extract template file path from user request
• Verify file exists
• Run: lvt parse <template-file>
• Check validation results
• If errors found, help user fix them
• If warnings, explain what they mean

Common Issues Found

Issue 1: Unclosed tags

Example: {{range .Items (missing }}) Fix: Close all template actions properly

Issue 2: Invalid function calls

Example: {{UnknownFunction}} Fix: Use built-in functions or kit helpers

Issue 3: Missing end tags

Example: {{range .Items}} without {{end}} Fix: Add matching {{end}} tag

Issue 4: Type mismatches

Example: {{.Count | add "text"}} Fix: Ensure function arguments match expected types

Issue 5: Undefined fields

Example: {{.NonExistentField}} Warning: Field might not exist in data structure

Template Syntax Reminder

Valid actions:

<!-- Variables -->
{{.FieldName}}
{{$var := .Value}}

<!-- Conditionals -->
{{if .Show}}...{{end}}
{{if .Show}}...{{else}}...{{end}}

<!-- Loops -->
{{range .Items}}
  {{.Name}}
{{end}}

<!-- With (context) -->
{{with .User}}
  {{.Name}}
{{end}}

<!-- Template inclusion -->
{{template "component" .}}

<!-- Functions/Pipes -->
{{.Title | uppercase}}
{{add .Count 1}}

Use Cases

1. Before deploying: Validate all templates
2. After customization: Ensure changes didn't break syntax
3. Debugging: Find syntax errors quickly
4. Learning: Understand template structure
5. CI/CD: Automated template validation

Notes

• Validates both html/template and LiveTemplate
• Execution test uses sample data (might not match real data)
• Execution errors might be OK if template expects specific data
• Can validate any .tmpl file, not just generated ones
• Catches most syntax errors before runtime
• Doesn't validate business logic or data correctness
• Fast validation (no server startup required)