@lightningjs/blits - npm Package Compare versions

Comparing version 0.4.1 to 0.4.2

boilerplate/package.json

@@ -34,4 +34,4 @@ {
   "dependencies": {
-    "@lightningjs/blits": "^0.4.1"
+    "@lightningjs/blits": "^0.4.2"
   }
 }

CHANGELOG.md

 # Changelog
 
+# v0.4.2
+
+_22 nov 2023_
+
+- Improved parser and added more template validation (i.e. one single root element in a template)
+- Fixed typo in documentation
+
 # v0.4.1
@@ -4,0 +11,0 @@

docs/watchers.md

@@ -28,3 +28,3 @@ # Blits - Lightning 3 App Development Framework
   },
-  watchers: {
+  watch: {
     alpha(value, oldValue) {
@@ -31,0 +31,0 @@ if(value > oldValue) {

package.json

 {
   "name": "@lightningjs/blits",
-  "version": "0.4.1",
+  "version": "0.4.2",
   "description": "Blits: The Lightning 3 App Development Framework",
@@ -5,0 +5,0 @@ "bin": "bin/index.cjs",

src/lib/templateparser/parser.js

@@ -22,3 +22,3 @@ /*
   constructor(message, name, context) {
-    super(`TemplateParseError ${message}`)
+    super(`TemplateParseError: ${message}`)
     this.name = name
@@ -45,5 +45,4 @@ this.context = context
     template = clean(template)
-    parseLoop(parseEmptyTagStart)
-
     try {
+      parseLoop(parseEmptyTagStart)
       return format(tags)
@@ -128,2 +127,6 @@ } catch (error) {
       if (match[1] === '/>') {
+        if (currentTag[symbols.type] === 'closing') {
+          // 10 is arbitrary, just to show some context by moving the cursor back a bit
+          throw new TemplateParseError('InvalidClosingTag', template.slice(cursor - 10))
+        }
         currentTag[symbols.type] = 'self-closing'
@@ -180,79 +183,90 @@ currentLevel-- // because it was parsed as opening tag before
 
-  // formatter
-  function format(data) {
+  // formating and validation
+
+  /*
+  validation rules:
+    #1: Every opening tag must have a corresponding closing tag at the same level. If a closing tag is encountered without
+        a preceding opening tag at the same level, or if an opening tag is not followed by a corresponding closing tag at
+        the same level, an error should be thrown.
+    #2: There must be exactly one top-level element (an element at level 0). This element may either be a self-closing
+        element or an opening tag followed by a closing tag. If more than one top-level element is encountered, an error
+        should be thrown.
+  */
+  const format = (parsedData) => {
     let stack = []
+    let rootElementDefined = false
     let output = { children: [] }
+    let currentParent = output
 
-    for (const item of data) {
-      const { type, [symbols.type]: __type, [symbols.level]: __level } = item
+    for (let i = 0; i < parsedData.length; i++) {
+      let element = parsedData[i]
 
-      // Check for unclosed tags
-      while (stack.length && stack[stack.length - 1][symbols.level] >= __level) {
-        const popped = stack.pop()
-        if (popped[symbols.type] === 'opening') {
-          throw new TemplateParseError('MismatchedClosingTag', `tag: ${popped.type || 'null'}`)
+      // Rule #1
+      if (element[symbols.level] === 0 && element[symbols.type] !== 'closing') {
+        if (rootElementDefined) {
+          throw new TemplateParseError('MultipleTopLevelTags', formatErrorContext(element))
         }
+        rootElementDefined = true
       }
 
-      // For closing tags, just pop the opening tag from stack and continue
-      if (__type === 'closing') {
-        let lastStackType = stack[stack.length - 1] ? stack[stack.length - 1].type : null
+      // Rule #2
+      if (element[symbols.type] === 'opening') {
+        stack.push({
+          [symbols.level]: element[symbols.level],
+          [symbols.type]: element[symbols.type],
+          type: element.type,
+          parent: currentParent, // helps getting the previous parent when closing tag is encountered
+        })
+      } else if (element[symbols.type] === 'closing') {
+        const isStackEmpty = stack.length === 0
+        let isLevelMismatch = false
+        let isTagMismatch = false
+        if (!isStackEmpty) {
+          isLevelMismatch = stack[stack.length - 1][symbols.level] !== element[symbols.level]
+          isTagMismatch = stack[stack.length - 1].type !== element.type
+        }
 
-        if (
-          stack.length === 0 ||
-          (type
-            ? lastStackType && lastStackType.toLowerCase() !== type.toLowerCase()
-            : lastStackType !== null)
-        ) {
-          throw new TemplateParseError('MismatchedClosingTag', `tag: ${type || 'null'}`)
+        if (isStackEmpty || isLevelMismatch || isTagMismatch) {
+          throw new TemplateParseError('MismatchedClosingTag', formatErrorContext(element))
         }
-        stack.pop()
-        continue
+
+        // when we remove the closing element from the stack, we should set
+        // the current parent to the parent of the closing element
+        const lastTag = stack.pop()
+        currentParent = lastTag.parent
       }
 
-      // Create a new item, copying properties but deleting __type and __level
-      const newItem = { ...item }
+      const newItem = { ...element }
       delete newItem[symbols.type]
       delete newItem[symbols.level]
 
-      if (__type === 'opening') {
-        newItem.children = []
-      }
-
-      // Find out where to insert this new item
-      let current = output.children
-      for (const stackItem of stack) {
-        if (stackItem.children) {
-          current = stackItem.children
+      // if it is an opening tag, add children[] to it and update current parent
+      if (element[symbols.type] === 'opening') {
+        // make sure the current opening tag has really a child element
+        if (i + 1 < parsedData.length && parsedData[i + 1][symbols.type] !== 'closing') {
+          newItem.children = []
         }
+        currentParent.children.push(newItem)
+        currentParent = newItem
+      } else if (element[symbols.type] === 'self-closing') {
+        currentParent.children.push(newItem)
       }
-
-      // Insert the item and push it to the stack
-      current.push(newItem)
-      stack.push(newItem)
-
-      // If this is a self-closing tag, immediately pop it off the stack
-      if (__type === 'self-closing') {
-        stack.pop()
-      }
     }
 
-    // Check for any remaining unclosed tags
-    for (const item of stack) {
-      if (item.__type === 'opening') {
-        throw new TemplateParseError('MismatchedClosingTag', `tag: ${item.type || 'null'}`)
-      }
+    // Check if all tags are closed (so stack should be empty)[Rule #1]
+    if (stack.length > 0) {
+      const unclosedTags = stack
+        .map((item) => {
+          return formatErrorContext(item)
+        })
+        .join(', ')
+      throw new TemplateParseError('UnclosedTags', unclosedTags)
     }
 
-    // Remove empty 'children' arrays
-    function removeEmptyChildren(obj, level = 0) {
-      if (Array.isArray(obj.children) && obj.children.length === 0 && level > 0) {
-        delete obj.children
-      }
-      if (obj.children) {
-        obj.children.forEach((child) => removeEmptyChildren(child, level + 1))
-      }
+    function formatErrorContext(element) {
+      return `${element.type || 'empty-tag'}[${element[symbols.type]}] at level ${
+        element[symbols.level]
+      }`
     }
 
-    removeEmptyChildren(output)
     return output
@@ -259,0 +273,0 @@ }

src/lib/templateparser/parser.test.js

@@ -950,1 +950,100 @@ /*
 })
+
+test('Parse template with multiple top level elements and parsing should fail', (assert) => {
+  const template = `
+  <Component>
+    <Element
+      w='160' h="160" x='40' y='40' color="#fb923c"
+      :effects='[$shader(
+        "radius",
+        {radius: 44}
+      )]'
+    />
+  </Component>
+  <Component>
+    <Element
+      w='120' h="120"
+      x='100' y="100"
+      :effects="[
+        $shader(
+          'radius',
+          {
+            radius: 45
+          }
+        )
+      ]"
+    />
+  </Component>`
+
+  const actual = parser(template)
+  assert.equal(actual, null, 'Parser should throw an error')
+
+  assert.end()
+})
+
+test('Parse template with unclosed tag and parsing should fail', (assert) => {
+  const template = `
+  <Component>
+    <Element>
+  </Component>
+  `
+
+  const actual = parser(template)
+  assert.equal(actual, null, 'Parser should throw an error')
+  assert.end()
+})
+
+test('Parse template with multiple unclosed tags and parsing should fail', (assert) => {
+  const template = `
+  <Component>
+    <Element>
+      <Button />
+      <Text>Lorem Ipsum</Text>
+      <Element>
+        <Button />
+        <Text>Lorem Ipsum</Text>
+  </Component>
+  `
+
+  const actual = parser(template)
+  assert.equal(actual, null, 'Parser should throw an error')
+  assert.end()
+})
+
+test('Parse template with an invalid closing tag and parsing should fail', (assert) => {
+  const template = `
+  <Component>
+    <Element>
+    </Element/>
+  </Component>
+  `
+
+  const actual = parser(template)
+  assert.equal(actual, null, 'Parser should throw an error')
+
+  assert.end()
+})
+
+test('Parse template with multiple self-closing tags at the top level and parsing should fail', (assert) => {
+  const template = `
+  <Component/>
+  <Element/>
+  `
+
+  const actual = parser(template)
+  assert.equal(actual, null, 'Parser should throw an error')
+  assert.end()
+})
+
+test('Parse template with a closing tag at the beginning and parsing should fail', (assert) => {
+  const template = `
+  </Element>
+  <Component>
+    <Element/>
+  </Component>
+  `
+
+  const actual = parser(template)
+  assert.equal(actual, null, 'Parser should throw an error')
+  assert.end()
+})

No alert changes

Improved metrics

Total package byte prevSize

904228

increased by0.39%

Lines of code

22136

increased by0.46%

No dependency changes