limit parsing and detected cache

Author: joetannenbaum

src/extension.ts

@@ -26,7 +26,7 @@ import {
     watchForComposerChanges,
 } from "./support/fileWatcher";
 import { info } from "./support/logger";
-import { setParserBinaryPath } from "./support/parser";
+import { clearParserCaches, setParserBinaryPath } from "./support/parser";
 import { clearDefaultPhpCommand, initVendorWatchers } from "./support/php";
 import { hasWorkspace, projectPathExists } from "./support/project";
 import { cleanUpTemp } from "./support/util";
@@ -185,6 +185,7 @@ export function deactivate() {
     }
 
     disposeWatchers();
+    clearParserCaches();
 
     if (client) {
         client.stop();

src/support/cache.ts

@@ -0,0 +1,46 @@
+export class Cache<K, V> {
+    private maxSize: number;
+    private cache: Map<K, V>;
+
+    constructor(maxSize: number) {
+        this.maxSize = maxSize;
+        this.cache = new Map();
+    }
+
+    get(key: K): V | undefined {
+        const value = this.cache.get(key);
+
+        if (value !== undefined) {
+            this.cache.delete(key);
+            this.cache.set(key, value);
+        }
+
+        return value;
+    }
+
+    set(key: K, value: V): void {
+        if (this.cache.has(key)) {
+            this.cache.delete(key);
+        } else if (this.cache.size >= this.maxSize) {
+            const firstKey = this.cache.keys().next().value;
+
+            if (firstKey !== undefined) {
+                this.cache.delete(firstKey);
+            }
+        }
+
+        this.cache.set(key, value);
+    }
+
+    has(key: K): boolean {
+        return this.cache.has(key);
+    }
+
+    clear(): void {
+        this.cache.clear();
+    }
+
+    size(): number {
+        return this.cache.size;
+    }
+}

src/support/parser.ts

@@ -9,14 +9,20 @@ import * as fs from "fs";
 import * as os from "os";
 import * as vscode from "vscode";
 import { FeatureTag, ValidDetectParamTypes } from "..";
+import { Cache } from "./cache";
 import { showErrorPopup } from "./popup";
 import { md5, tempPath, toArray } from "./util";
 
-const currentlyParsing = new Map<string, Promise<AutocompleteResult>>();
-const detected = new Map<
+const currentlyParsing = new Cache<string, Promise<AutocompleteResult>>(100);
+const detected = new Cache<
     string,
     Promise<AutocompleteParsingResult.ContextValue[]>
->();
+>(50);
+
+export const clearParserCaches = (): void => {
+    currentlyParsing.clear();
+    detected.clear();
+};
 
 type TokenFormatted = [string, string, number];
 type Token = string | TokenFormatted;