Rewrite TokenizedBufferIterator in js

2026-04-28 03:01:47 -04:00 · 2016-09-27 07:37:12 -07:00
parent b71b412ede
commit 853130f581
2 changed files with 165 additions and 126 deletions
--- a/src/tokenized-buffer-iterator.js
+++ b/src/tokenized-buffer-iterator.js
@@ -0,0 +1,165 @@
+const {Point} = require('text-buffer')
+
+module.exports = class TokenizedBufferIterator {
+  constructor(tokenizedBuffer) {
+    this.tokenizedBuffer = tokenizedBuffer
+    this.openTags = null
+    this.closeTags = null
+    this.containingTags = null
+  }
+
+  seek(position) {
+    this.openTags = []
+    this.closeTags = []
+    this.tagIndex = null
+
+    const currentLine = this.tokenizedBuffer.tokenizedLineForRow(position.row)
+    this.currentTags = currentLine.tags
+    this.currentLineOpenTags = currentLine.openScopes
+    this.currentLineLength = currentLine.text.length
+    this.containingTags = this.currentLineOpenTags.map(id => this.tokenizedBuffer.grammar.scopeForId(id))
+
+    let currentColumn = 0
+    for (let [index, tag] of this.currentTags.entries()) {
+      if (tag >= 0) {
+        if (currentColumn >= position.column) {
+          this.tagIndex = index
+          break
+        } else {
+          currentColumn += tag
+          while (this.closeTags.length > 0) {
+            this.closeTags.shift()
+            this.containingTags.pop()
+          }
+          while (this.openTags.length > 0) {
+            const openTag = this.openTags.shift()
+            this.containingTags.push(openTag)
+          }
+        }
+      } else {
+        const scopeName = this.tokenizedBuffer.grammar.scopeForId(tag)
+        if (tag % 2 === 0) {
+          if (this.openTags.length > 0) {
+            if (currentColumn >= position.column) {
+              this.tagIndex = index
+              break
+            } else {
+              while (this.closeTags.length > 0) {
+                this.closeTags.shift()
+                this.containingTags.pop()
+              }
+              while (this.openTags.length > 0) {
+                const openTag = this.openTags.shift()
+                this.containingTags.push(openTag)
+              }
+            }
+          }
+          this.closeTags.push(scopeName)
+        } else {
+          this.openTags.push(scopeName)
+        }
+      }
+    }
+
+    if (this.tagIndex == null) {
+      this.tagIndex = this.currentTags.length
+    }
+    this.position = Point(position.row, Math.min(this.currentLineLength, currentColumn))
+    return this.containingTags.slice()
+  }
+
+  moveToSuccessor() {
+    for (let tag of this.closeTags) {
+      this.containingTags.pop()
+    }
+    for (let tag of this.openTags) {
+      this.containingTags.push(tag)
+    }
+    this.openTags = []
+    this.closeTags = []
+    while (true) {
+      if (this.tagIndex === this.currentTags.length) {
+        if (this.isAtTagBoundary()) {
+          break
+        } else if (this.shouldMoveToNextLine) {
+          this.moveToNextLine()
+          this.openTags = this.currentLineOpenTags.map(id => this.tokenizedBuffer.grammar.scopeForId(id))
+          this.shouldMoveToNextLine = false
+        } else if (this.nextLineHasMismatchedContainingTags()) {
+          this.closeTags = this.containingTags.slice().reverse()
+          this.containingTags = []
+          this.shouldMoveToNextLine = true
+        } else if (!this.moveToNextLine()) {
+          return false
+        }
+      } else {
+        const tag = this.currentTags[this.tagIndex]
+        if (tag >= 0) {
+          if (this.isAtTagBoundary()) {
+            break
+          } else {
+            this.position = Point(this.position.row, Math.min(
+              this.currentLineLength,
+              this.position.column + this.currentTags[this.tagIndex]
+            ))
+          }
+        } else {
+          const scopeName = this.tokenizedBuffer.grammar.scopeForId(tag)
+          if (tag % 2 === 0) {
+            if (this.openTags.length > 0) {
+              break
+            } else {
+              this.closeTags.push(scopeName)
+            }
+          } else {
+            this.openTags.push(scopeName)
+          }
+        }
+        this.tagIndex++
+      }
+    }
+    return true
+  }
+
+  getPosition() {
+    return this.position
+  }
+
+  getCloseTags() {
+    return this.closeTags.slice()
+  }
+
+  getOpenTags() {
+    return this.openTags.slice()
+  }
+
+  nextLineHasMismatchedContainingTags() {
+    const line = this.tokenizedBuffer.tokenizedLineForRow(this.position.row + 1)
+    if (line == null) {
+      return false
+    } else {
+      return (
+        this.containingTags.length !== line.openScopes.length ||
+        this.containingTags.some((tag, i) => tag !== this.tokenizedBuffer.grammar.scopeForId(line.openScopes[i]))
+      )
+    }
+  }
+
+  moveToNextLine() {
+    this.position = Point(this.position.row + 1, 0)
+    const tokenizedLine = this.tokenizedBuffer.tokenizedLineForRow(this.position.row)
+    if (tokenizedLine == null) {
+      return false
+    } else {
+      this.currentTags = tokenizedLine.tags
+      this.currentLineLength = tokenizedLine.text.length
+      this.currentLineOpenTags = tokenizedLine.openScopes
+      this.tagIndex = 0
+      return true
+    }
+  }
+
+  isAtTagBoundary() {
+    return this.closeTags.length > 0 || this.openTags.length > 0
+  }
+}