add TextDocument tests for invalid inputs (#1286)

* add TextDocument tests for invalid inputs * TextDocument.positionAt and offsetAt incorrectly include line endings * polish --------- Co-authored-by: Dirk Bäumer <dirkb@microsoft.com> Co-authored-by: Martin Aeschlimann <martinae@microsoft.com>
microsoft · Jul 30, 2024 · 04d7162 · 04d7162
1 parent 046423e
commit 04d7162
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diff --git a/textDocument/src/main.ts b/textDocument/src/main.ts
@@ -297,6 +297,8 @@ class FullTextDocument implements TextDocument {
 		// low is the least x for which the line offset is larger than the current offset
 		// or array.length if no line offset is larger than the current offset
 		const line = low - 1;
+
+		offset = this.ensureBeforeEOL(offset, lineOffsets[line]);
 		return { line, character: offset - lineOffsets[line] };
 	}
 
@@ -308,8 +310,20 @@ class FullTextDocument implements TextDocument {
 			return 0;
 		}
 		const lineOffset = lineOffsets[position.line];
+		if (position.character <= 0) {
+			return lineOffset;
+		}
+
 		const nextLineOffset = (position.line + 1 < lineOffsets.length) ? lineOffsets[position.line + 1] : this._content.length;
-		return Math.max(Math.min(lineOffset + position.character, nextLineOffset), lineOffset);
+		const offset = Math.min(lineOffset + position.character, nextLineOffset);
+		return this.ensureBeforeEOL(offset, lineOffset);
+	}
+
+	private ensureBeforeEOL(offset: number, lineOffset: number): number {
+		while (offset > lineOffset && isEOL(this._content.charCodeAt(offset - 1))) {
+			offset--;
+		}
+		return offset;
 	}
 
 	public get lineCount() {
@@ -438,7 +452,7 @@ function computeLineOffsets(text: string, isAtLineStart: boolean, textOffset = 0
 	const result: number[] = isAtLineStart ? [textOffset] : [];
 	for (let i = 0; i < text.length; i++) {
 		const ch = text.charCodeAt(i);
-		if (ch === CharCode.CarriageReturn || ch === CharCode.LineFeed) {
+		if (isEOL(ch)) {
 			if (ch === CharCode.CarriageReturn && i + 1 < text.length && text.charCodeAt(i + 1) === CharCode.LineFeed) {
 				i++;
 			}
@@ -448,6 +462,10 @@ function computeLineOffsets(text: string, isAtLineStart: boolean, textOffset = 0
 	return result;
 }
 
+function isEOL(char: number) {
+	return char === CharCode.CarriageReturn || char === CharCode.LineFeed;
+}
+
 function getWellformedRange(range: Range): Range {
 	const start = range.start;
 	const end = range.end;

diff --git a/textDocument/src/test/textdocument.test.ts b/textDocument/src/test/textdocument.test.ts
@@ -63,23 +63,32 @@ suite('Text Document Lines Model Validator', () => {
 	});
 
 	test('New line characters', () => {
-		let str = 'ABCDE\rFGHIJ';
-		assert.equal(newDocument(str).lineCount, 2);
+		let document = newDocument('ABCDE\rFGHIJ');
+		assert.equal(document.lineCount, 2);
+		assert.equal(document.offsetAt(Positions.create(1, 0)), 6);
 
-		str = 'ABCDE\nFGHIJ';
-		assert.equal(newDocument(str).lineCount, 2);
+		document = newDocument('ABCDE\nFGHIJ');
+		assert.equal(document.lineCount, 2);
+		assert.equal(document.offsetAt(Positions.create(1, 0)), 6);
 
-		str = 'ABCDE\r\nFGHIJ';
-		assert.equal(newDocument(str).lineCount, 2);
+		document = newDocument('ABCDE\r\nFGHIJ');
+		assert.equal(document.lineCount, 2);
+		assert.equal(document.offsetAt(Positions.create(1, 0)), 7);
 
-		str = 'ABCDE\n\nFGHIJ';
-		assert.equal(newDocument(str).lineCount, 3);
+		document = newDocument('ABCDE\n\nFGHIJ');
+		assert.equal(document.lineCount, 3);
+		assert.equal(document.offsetAt(Positions.create(1, 0)), 6);
+		assert.equal(document.offsetAt(Positions.create(2, 0)), 7);
 
-		str = 'ABCDE\r\rFGHIJ';
-		assert.equal(newDocument(str).lineCount, 3);
+		document = newDocument('ABCDE\r\rFGHIJ');
+		assert.equal(document.lineCount, 3);
+		assert.equal(document.offsetAt(Positions.create(1, 0)), 6);
+		assert.equal(document.offsetAt(Positions.create(2, 0)), 7);
 
-		str = 'ABCDE\n\rFGHIJ';
-		assert.equal(newDocument(str).lineCount, 3);
+		document = newDocument('ABCDE\n\rFGHIJ');
+		assert.equal(document.lineCount, 3);
+		assert.equal(document.offsetAt(Positions.create(1, 0)), 6);
+		assert.equal(document.offsetAt(Positions.create(2, 0)), 7);
 	});
 
 	test('getText(Range)', () => {
@@ -94,22 +103,47 @@ suite('Text Document Lines Model Validator', () => {
 		assert.equal(document.getText(Ranges.create(0, 0, 3, 5)), str);
 	});
 
-	test('Invalid inputs', () => {
-		const str = 'Hello World';
-		const document = newDocument(str);
+	test('Invalid inputs at beginning of file', () => {
+		let document = newDocument('ABCDE');
+		assert.equal(document.offsetAt(Positions.create(-1, 0)), 0);
+		assert.equal(document.offsetAt(Positions.create(0, -1)), 0);
+		assert.deepEqual(document.positionAt(-1), Positions.create(0, 0));
+	});
 
-		// invalid position
-		assert.equal(document.offsetAt(Positions.create(0, str.length)), str.length);
-		assert.equal(document.offsetAt(Positions.create(0, str.length + 3)), str.length);
-		assert.equal(document.offsetAt(Positions.create(2, 3)), str.length);
-		assert.equal(document.offsetAt(Positions.create(-1, 3)), 0);
-		assert.equal(document.offsetAt(Positions.create(0, -3)), 0);
-		assert.equal(document.offsetAt(Positions.create(1, -3)), str.length);
+	test('Invalid inputs at end of file', () => {
+		let str = 'ABCDE\n';
+		let document = newDocument(str);
+		assert.equal(document.offsetAt(Positions.create(1, 1)), str.length);
+		assert.equal(document.offsetAt(Positions.create(2, 0)), str.length);
+		assert.deepEqual(document.positionAt(str.length), Positions.create(1, 0));
+		assert.deepEqual(document.positionAt(str.length + 3), Positions.create(1, 0));
+
+		str = 'ABCDE';
+		document = newDocument(str);
+		assert.equal(document.offsetAt(Positions.create(0, 10)), str.length);
+		assert.equal(document.offsetAt(Positions.create(1, 1)), str.length);
+		assert.deepEqual(document.positionAt(str.length), Positions.create(0, 5));
+		assert.deepEqual(document.positionAt(str.length + 3), Positions.create(0, 5));
+	});
 
-		// invalid offsets
-		assert.deepEqual(document.positionAt(-1), Positions.create(0, 0));
-		assert.deepEqual(document.positionAt(str.length), Positions.create(0, str.length));
-		assert.deepEqual(document.positionAt(str.length + 3), Positions.create(0, str.length));
+	test('Invalid inputs at beginning of line', () => {
+		let document = newDocument('A\nB\rC\r\nD');
+		assert.equal(document.offsetAt(Positions.create(0, -1)), 0);
+		assert.equal(document.offsetAt(Positions.create(1, -1)), 2);
+		assert.equal(document.offsetAt(Positions.create(2, -1)), 4);
+		assert.equal(document.offsetAt(Positions.create(3, -1)), 7);
+	});
+
+	test('Invalid inputs at end of line', () => {
+		let document = newDocument('A\nB\rC\r\nD');
+		assert.equal(document.offsetAt(Positions.create(0, 10)), 1);
+		assert.equal(document.offsetAt(Positions.create(1, 10)), 3);
+		assert.equal(document.offsetAt(Positions.create(2, 2)), 5); // between \r and \n
+		assert.equal(document.offsetAt(Positions.create(2, 3)), 5);
+		assert.equal(document.offsetAt(Positions.create(2, 10)), 5);
+		assert.equal(document.offsetAt(Positions.create(3, 10)), 8);
+
+		assert.deepEqual(document.positionAt(6), Positions.create(2, 1)); // between \r and \n
 	});
 });