Add input range tracking for AstNode

pgonzal · pgonzal · commit 3f6acf745053 · 2018-08-21T11:42:29.000-07:00
diff --git a/libraries/rushell/src/AstNode.ts b/libraries/rushell/src/AstNode.ts
@@ -2,6 +2,7 @@
 // See LICENSE in the project root for license information.
 
 import { Token } from './Tokenizer';
+import { TextRange } from './TextRange';
 
 export enum AstKind {
   None,
@@ -18,27 +19,29 @@ export enum AstKind {
  */
 export abstract class AstBaseNode {
   public readonly kind: AstKind = AstKind.None;
+  public range: TextRange | undefined;
 
   /**
    * Returns a diagnostic dump of the tree, showing the prefix/suffix/separator for
    * each node.
    */
   public getDump(indent: string = ''): string {
-    let result: string = indent + AstKind[this.kind];
+    const nestedIndent: string = indent + '  ';
+    let result: string = indent + '- ' + AstKind[this.kind] + ':\n';
 
     const dumpText: string | undefined = this.getDumpText();
     if (dumpText) {
-      result += '=' + JSON.stringify(dumpText);
+      result += nestedIndent + 'Value=' + JSON.stringify(dumpText) + '\n';
+    }
+
+    const fullRange: TextRange = this.getFullRange();
+    if (!fullRange.isEmpty()) {
+      result += nestedIndent + 'Range=' + JSON.stringify(fullRange.toString()) + '\n';
     }
 
     const childNodes: AstBaseNode[] = this.getChildNodes();
-    if (childNodes.length === 0) {
-      result += '\n';
-    } else {
-      result += ':\n';
-      for (const child of this.getChildNodes()) {
-        result += child.getDump(indent + '  ');
-      }
+    for (const child of childNodes) {
+      result += child.getDump(nestedIndent);
     }
 
     return result;
@@ -50,6 +53,20 @@ export abstract class AstBaseNode {
     return nodes;
   }
 
+  public getFullRange(): TextRange {
+    if (this.range) {
+      return this.range;
+    }
+
+    let encompassingRange: TextRange = TextRange.empty;
+
+    for (const child of this.getChildNodes()) {
+      encompassingRange = encompassingRange.getEncompassingRange(child.getFullRange());
+    }
+
+    return encompassingRange;
+  }
+
   protected abstract collectChildNodesInto(nodes: AstBaseNode[]): void;
 
   protected getDumpText(): string | undefined {
diff --git a/libraries/rushell/src/Parser.ts b/libraries/rushell/src/Parser.ts
@@ -93,6 +93,7 @@ export class Parser {
 
       const astText: AstText = new AstText();
       astText.token = token;
+      astText.range = token.range;
       return astText;
     }
 
diff --git a/libraries/rushell/src/TextRange.ts b/libraries/rushell/src/TextRange.ts
@@ -65,6 +65,45 @@ export class TextRange {
     return new TextRange(this.buffer, pos, end);
   }
 
+  public isEmpty(): boolean {
+    return this.pos === this.end;
+  }
+
+  /**
+   * Returns the smallest TextRange object that encompasses both ranges.  If there is a gap
+   * between the two ranges, it will be included in the encompassing range.
+   */
+  public getEncompassingRange(other: TextRange): TextRange {
+    let newBuffer: string = this.buffer;
+
+    // Allow combining TextRange.empty with a TextRange from a different buffer
+    if (other.buffer.length > 0) {
+      newBuffer = other.buffer;
+
+      if (this.buffer.length > 0) {
+        if (this.buffer !== other.buffer) {
+          throw new Error('The ranges cannot be combined because they come from different buffers');
+        }
+      }
+    }
+
+    let newPos: number = this.pos;
+    let newEnd: number = this.end;
+
+    if (!other.isEmpty()) {
+      if (this.isEmpty()) {
+        newPos = other.pos;
+        newEnd = other.end;
+      } else {
+        // Neither range is empty, so combine them
+        newPos = Math.min(other.pos, this.pos);
+        newEnd = Math.max(other.end, this.end);
+      }
+    }
+
+    return new TextRange(newBuffer, newPos, newEnd);
+  }
+
   /**
    * Returns the range from the associated string buffer.
    */
diff --git a/libraries/rushell/src/test/Parser.test.ts b/libraries/rushell/src/test/Parser.test.ts
@@ -18,7 +18,7 @@ function matchSnapshot(input: string): void {
   const result: AstScript = parser.parse();
   expect({
     input: escape(tokenizer.input.toString()),
-    tree: result.getDump()
+    tree: '\n' + result.getDump()
   }).toMatchSnapshot();
 }
 
diff --git a/libraries/rushell/src/test/__snapshots__/Parser.test.ts.snap b/libraries/rushell/src/test/__snapshots__/Parser.test.ts.snap
@@ -3,14 +3,26 @@
 exports[`00: basic inputs 1`] = `
 Object {
   "input": "command arg1 arg2",
-  "tree": "Script:
-  Command:
-    CompoundWord:
-      Text=\\"command\\"
-    CompoundWord:
-      Text=\\"arg1\\"
-    CompoundWord:
-      Text=\\"arg2\\"
+  "tree": "
+- Script:
+  Range=\\"command arg1 arg2\\"
+  - Command:
+    Range=\\"command arg1 arg2\\"
+    - CompoundWord:
+      Range=\\"command\\"
+      - Text:
+        Value=\\"command\\"
+        Range=\\"command\\"
+    - CompoundWord:
+      Range=\\"arg1\\"
+      - Text:
+        Value=\\"arg1\\"
+        Range=\\"arg1\\"
+    - CompoundWord:
+      Range=\\"arg2\\"
+      - Text:
+        Value=\\"arg2\\"
+        Range=\\"arg2\\"
 ",
 }
 `;

Original file line number	Diff line number	Diff line change
`@@ -93,6 +93,7 @@ export class Parser {`
`93`	`93`
`94`	`94`	`const astText: AstText = new AstText();`
`95`	`95`	`astText.token = token;`
	`96`	`+ astText.range = token.range;`
`96`	`97`	`return astText;`
`97`	`98`	`}`
`98`	`99`
Original file line number	Diff line number	Diff line change
`@@ -18,7 +18,7 @@ function matchSnapshot(input: string): void {`
`18`	`18`	`const result: AstScript = parser.parse();`
`19`	`19`	`expect({`
`20`	`20`	`input: escape(tokenizer.input.toString()),`
`21`		`- tree: result.getDump()`
	`21`	`+ tree: '\n' + result.getDump()`
`22`	`22`	`}).toMatchSnapshot();`
`23`	`23`	`}`
`24`	`24`