Extract shared helper

Author: amcasey

src/compiler/program.ts

@@ -103,31 +103,20 @@ namespace ts {
             return false;
         }
 
-        function ensureDirectoriesExist(directoryPath: string) {
-            if (directoryPath.length > getRootLength(directoryPath) && !directoryExists(directoryPath)) {
-                const parentDirectory = getDirectoryPath(directoryPath);
-                ensureDirectoriesExist(parentDirectory);
-                (compilerHost.createDirectory || system.createDirectory)(directoryPath);
-            }
-        }
-
         function writeFile(fileName: string, data: string, writeByteOrderMark: boolean, onError?: (message: string) => void) {
             try {
                 performance.mark("beforeIOWrite");
 
-                // PERF: Checking for directory existence is expensive.
-                // Instead, assume the directory exists and fall back
-                // to creating it if the file write fails.
                 // NOTE: If patchWriteFileEnsuringDirectory has been called,
-                // the file write will do its own directory creation and
+                // the system.writeFile will do its own directory creation and
                 // the ensureDirectoriesExist call will always be redundant.
-                try {
-                    writeFileWorker(fileName, data, writeByteOrderMark);
-                }
-                catch {
-                    ensureDirectoriesExist(getDirectoryPath(normalizePath(fileName)));
-                    writeFileWorker(fileName, data, writeByteOrderMark);
-                }
+                writeFileEnsuringDirectories(
+                    fileName,
+                    data,
+                    writeByteOrderMark,
+                    writeFileWorker,
+                    compilerHost.createDirectory || system.createDirectory,
+                    directoryExists);
 
                 performance.mark("afterIOWrite");
                 performance.measure("I/O Write", "beforeIOWrite", "afterIOWrite");

src/compiler/sys.ts

@@ -522,40 +522,21 @@ namespace ts {
         }
     }
 
-    function recursiveCreateDirectory(directoryPath: string, sys: System) {
-        const basePath = getDirectoryPath(directoryPath);
-        const shouldCreateParent = basePath !== "" && directoryPath !== basePath && !sys.directoryExists(basePath);
-        if (shouldCreateParent) {
-            recursiveCreateDirectory(basePath, sys);
-        }
-        if (shouldCreateParent || !sys.directoryExists(directoryPath)) {
-            sys.createDirectory(directoryPath);
-        }
-    }
-
     /**
      * patch writefile to create folder before writing the file
      */
     /*@internal*/
     export function patchWriteFileEnsuringDirectory(sys: System) {
         // patch writefile to create folder before writing the file
         const originalWriteFile = sys.writeFile;
-        sys.writeFile = (path, data, writeBom) => {
-            // PERF: Checking for directory existence is expensive.
-            // Instead, assume the directory exists and fall back
-            // to creating it if the file write fails.
-            try {
-                originalWriteFile.call(sys, path, data, writeBom);
-            }
-            catch {
-                const directoryPath = getDirectoryPath(normalizeSlashes(path));
-                if (directoryPath && !sys.directoryExists(directoryPath)) {
-                    recursiveCreateDirectory(directoryPath, sys);
-                }
-
-                originalWriteFile.call(sys, path, data, writeBom);
-            }
-        };
+        sys.writeFile = (path, data, writeBom) =>
+            writeFileEnsuringDirectories(
+                path,
+                data,
+                writeBom,
+                (p, d, w) => originalWriteFile.call(sys, p, d, w),
+                sys.createDirectory,
+                sys.directoryExists);
     }
 
     /*@internal*/

src/compiler/utilities.ts

@@ -3700,6 +3700,36 @@ namespace ts {
         }, sourceFiles);
     }
 
+    function ensureDirectoriesExist(
+        directoryPath: string,
+        createDirectory: (path: string) => void,
+        directoryExists: (path: string) => boolean): void {
+        if (directoryPath.length > getRootLength(directoryPath) && !directoryExists(directoryPath)) {
+            const parentDirectory = getDirectoryPath(directoryPath);
+            ensureDirectoriesExist(parentDirectory, createDirectory, directoryExists);
+            createDirectory(directoryPath);
+        }
+    }
+
+    export function writeFileEnsuringDirectories(
+        path: string,
+        data: string,
+        writeByteOrderMark: boolean | undefined,
+        writeFile: (path: string, data: string, writeByteOrderMark?: boolean) => void,
+        createDirectory: (path: string) => void,
+        directoryExists: (path: string) => boolean): void {
+
+        // PERF: Checking for directory existence is expensive.  Instead, assume the directory exists
+        // and fall back to creating it if the file write fails.
+        try {
+            writeFile(path, data, writeByteOrderMark);
+        }
+        catch {
+            ensureDirectoriesExist(getDirectoryPath(normalizePath(path)), createDirectory, directoryExists);
+            writeFile(path, data, writeByteOrderMark);
+        }
+    }
+
     export function getLineOfLocalPosition(currentSourceFile: SourceFile, pos: number) {
         return getLineAndCharacterOfPosition(currentSourceFile, pos).line;
     }

src/compiler/watch.ts

@@ -296,31 +296,14 @@ namespace ts {
             readDirectory: maybeBind(host, host.readDirectory),
         };
 
-        function ensureDirectoriesExist(directoryPath: string) {
-            if (directoryPath.length > getRootLength(directoryPath) && !host.directoryExists!(directoryPath)) {
-                const parentDirectory = getDirectoryPath(directoryPath);
-                ensureDirectoriesExist(parentDirectory);
-                if (host.createDirectory) host.createDirectory(directoryPath);
-            }
-        }
-
         function writeFile(fileName: string, text: string, writeByteOrderMark: boolean, onError: (message: string) => void) {
             try {
                 performance.mark("beforeIOWrite");
 
-                // PERF: Checking for directory existence is expensive.
-                // Instead, assume the directory exists and fall back
-                // to creating it if the file write fails.
                 // NOTE: If patchWriteFileEnsuringDirectory has been called,
-                // the file write will do its own directory creation and
+                // the host.writeFile will do its own directory creation and
                 // the ensureDirectoriesExist call will always be redundant.
-                try {
-                    host.writeFile!(fileName, text, writeByteOrderMark);
-                }
-                catch {
-                    ensureDirectoriesExist(getDirectoryPath(normalizePath(fileName)));
-                    host.writeFile!(fileName, text, writeByteOrderMark);
-                }
+                writeFileEnsuringDirectories(fileName, text, writeByteOrderMark, host.writeFile!, host.createDirectory!, host.directoryExists!);
 
                 performance.mark("afterIOWrite");
                 performance.measure("I/O Write", "beforeIOWrite", "afterIOWrite");