Merge commit 'be3e8236086165e5e45a5a10783823874b3f3ebd' as 'lib/vscode'

lib/vscode/extensions/php-language-features/src/features/signatureHelpProvider.ts

@@ -0,0 +1,173 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { SignatureHelpProvider, SignatureHelp, SignatureInformation, CancellationToken, TextDocument, Position, workspace } from 'vscode';
+import phpGlobals = require('./phpGlobals');
+import phpGlobalFunctions = require('./phpGlobalFunctions');
+
+const _NL = '\n'.charCodeAt(0);
+const _TAB = '\t'.charCodeAt(0);
+const _WSB = ' '.charCodeAt(0);
+const _LBracket = '['.charCodeAt(0);
+const _RBracket = ']'.charCodeAt(0);
+const _LCurly = '{'.charCodeAt(0);
+const _RCurly = '}'.charCodeAt(0);
+const _LParent = '('.charCodeAt(0);
+const _RParent = ')'.charCodeAt(0);
+const _Comma = ','.charCodeAt(0);
+const _Quote = '\''.charCodeAt(0);
+const _DQuote = '"'.charCodeAt(0);
+const _USC = '_'.charCodeAt(0);
+const _a = 'a'.charCodeAt(0);
+const _z = 'z'.charCodeAt(0);
+const _A = 'A'.charCodeAt(0);
+const _Z = 'Z'.charCodeAt(0);
+const _0 = '0'.charCodeAt(0);
+const _9 = '9'.charCodeAt(0);
+
+const BOF = 0;
+
+
+class BackwardIterator {
+	private lineNumber: number;
+	private offset: number;
+	private line: string;
+	private model: TextDocument;
+
+	constructor(model: TextDocument, offset: number, lineNumber: number) {
+		this.lineNumber = lineNumber;
+		this.offset = offset;
+		this.line = model.lineAt(this.lineNumber).text;
+		this.model = model;
+	}
+
+	public hasNext(): boolean {
+		return this.lineNumber >= 0;
+	}
+
+	public next(): number {
+		if (this.offset < 0) {
+			if (this.lineNumber > 0) {
+				this.lineNumber--;
+				this.line = this.model.lineAt(this.lineNumber).text;
+				this.offset = this.line.length - 1;
+				return _NL;
+			}
+			this.lineNumber = -1;
+			return BOF;
+		}
+		let ch = this.line.charCodeAt(this.offset);
+		this.offset--;
+		return ch;
+	}
+
+}
+
+
+export default class PHPSignatureHelpProvider implements SignatureHelpProvider {
+
+	public provideSignatureHelp(document: TextDocument, position: Position, _token: CancellationToken): Promise<SignatureHelp> | null {
+		let enable = workspace.getConfiguration('php').get<boolean>('suggest.basic', true);
+		if (!enable) {
+			return null;
+		}
+
+		let iterator = new BackwardIterator(document, position.character - 1, position.line);
+
+		let paramCount = this.readArguments(iterator);
+		if (paramCount < 0) {
+			return null;
+		}
+
+		let ident = this.readIdent(iterator);
+		if (!ident) {
+			return null;
+		}
+
+		let entry = phpGlobalFunctions.globalfunctions[ident] || phpGlobals.keywords[ident];
+		if (!entry || !entry.signature) {
+			return null;
+		}
+		let paramsString = entry.signature.substring(0, entry.signature.lastIndexOf(')') + 1);
+		let signatureInfo = new SignatureInformation(ident + paramsString, entry.description);
+
+		let re = /\w*\s+\&?\$[\w_\.]+|void/g;
+		let match: RegExpExecArray | null = null;
+		while ((match = re.exec(paramsString)) !== null) {
+			signatureInfo.parameters.push({ label: match[0], documentation: '' });
+		}
+		let ret = new SignatureHelp();
+		ret.signatures.push(signatureInfo);
+		ret.activeSignature = 0;
+		ret.activeParameter = Math.min(paramCount, signatureInfo.parameters.length - 1);
+		return Promise.resolve(ret);
+	}
+
+	private readArguments(iterator: BackwardIterator): number {
+		let parentNesting = 0;
+		let bracketNesting = 0;
+		let curlyNesting = 0;
+		let paramCount = 0;
+		while (iterator.hasNext()) {
+			let ch = iterator.next();
+			switch (ch) {
+				case _LParent:
+					parentNesting--;
+					if (parentNesting < 0) {
+						return paramCount;
+					}
+					break;
+				case _RParent: parentNesting++; break;
+				case _LCurly: curlyNesting--; break;
+				case _RCurly: curlyNesting++; break;
+				case _LBracket: bracketNesting--; break;
+				case _RBracket: bracketNesting++; break;
+				case _DQuote:
+				case _Quote:
+					while (iterator.hasNext() && ch !== iterator.next()) {
+						// find the closing quote or double quote
+					}
+					break;
+				case _Comma:
+					if (!parentNesting && !bracketNesting && !curlyNesting) {
+						paramCount++;
+					}
+					break;
+			}
+		}
+		return -1;
+	}
+
+	private isIdentPart(ch: number): boolean {
+		if (ch === _USC || // _
+			ch >= _a && ch <= _z || // a-z
+			ch >= _A && ch <= _Z || // A-Z
+			ch >= _0 && ch <= _9 || // 0/9
+			ch >= 0x80 && ch <= 0xFFFF) { // nonascii
+
+			return true;
+		}
+		return false;
+	}
+
+	private readIdent(iterator: BackwardIterator): string {
+		let identStarted = false;
+		let ident = '';
+		while (iterator.hasNext()) {
+			let ch = iterator.next();
+			if (!identStarted && (ch === _WSB || ch === _TAB || ch === _NL)) {
+				continue;
+			}
+			if (this.isIdentPart(ch)) {
+				identStarted = true;
+				ident = String.fromCharCode(ch) + ident;
+			} else if (identStarted) {
+				return ident;
+			}
+		}
+		return ident;
+	}
+
+}