Runtime Compiler API (#3442)

Also restructures the compiler TypeScript files to make them easier to
manage and eventually integrate deno_typescript fully.

cli/js/util.ts

@@ -126,6 +126,7 @@ export function isObject(o: unknown): o is object {
 }
 
 // Returns whether o is iterable.
+// @internal
 export function isIterable<T, P extends keyof T, K extends T[P]>(
   o: T
 ): o is T & Iterable<[P, K]> {
@@ -224,6 +225,78 @@ export function splitNumberToParts(n: number): number[] {
   return [lower, higher];
 }
 
+// Constants used by `normalizeString` and `resolvePath`
+export const CHAR_DOT = 46; /* . */
+export const CHAR_FORWARD_SLASH = 47; /* / */
+
+/** Resolves `.` and `..` elements in a path with directory names */
+export function normalizeString(
+  path: string,
+  allowAboveRoot: boolean,
+  separator: string,
+  isPathSeparator: (code: number) => boolean
+): string {
+  let res = "";
+  let lastSegmentLength = 0;
+  let lastSlash = -1;
+  let dots = 0;
+  let code: number;
+  for (let i = 0, len = path.length; i <= len; ++i) {
+    if (i < len) code = path.charCodeAt(i);
+    else if (isPathSeparator(code!)) break;
+    else code = CHAR_FORWARD_SLASH;
+
+    if (isPathSeparator(code)) {
+      if (lastSlash === i - 1 || dots === 1) {
+        // NOOP
+      } else if (lastSlash !== i - 1 && dots === 2) {
+        if (
+          res.length < 2 ||
+          lastSegmentLength !== 2 ||
+          res.charCodeAt(res.length - 1) !== CHAR_DOT ||
+          res.charCodeAt(res.length - 2) !== CHAR_DOT
+        ) {
+          if (res.length > 2) {
+            const lastSlashIndex = res.lastIndexOf(separator);
+            if (lastSlashIndex === -1) {
+              res = "";
+              lastSegmentLength = 0;
+            } else {
+              res = res.slice(0, lastSlashIndex);
+              lastSegmentLength = res.length - 1 - res.lastIndexOf(separator);
+            }
+            lastSlash = i;
+            dots = 0;
+            continue;
+          } else if (res.length === 2 || res.length === 1) {
+            res = "";
+            lastSegmentLength = 0;
+            lastSlash = i;
+            dots = 0;
+            continue;
+          }
+        }
+        if (allowAboveRoot) {
+          if (res.length > 0) res += `${separator}..`;
+          else res = "..";
+          lastSegmentLength = 2;
+        }
+      } else {
+        if (res.length > 0) res += separator + path.slice(lastSlash + 1, i);
+        else res = path.slice(lastSlash + 1, i);
+        lastSegmentLength = i - lastSlash - 1;
+      }
+      lastSlash = i;
+      dots = 0;
+    } else if (code === CHAR_DOT && dots !== -1) {
+      ++dots;
+    } else {
+      dots = -1;
+    }
+  }
+  return res;
+}
+
 /** Return the common path shared by the `paths`.
  *
  * @param paths The set of paths to compare.
@@ -269,3 +342,14 @@ export function humanFileSize(bytes: number): string {
   } while (Math.abs(bytes) >= thresh && u < units.length - 1);
   return `${bytes.toFixed(1)} ${units[u]}`;
 }
+
+// @internal
+export function base64ToUint8Array(data: string): Uint8Array {
+  const binString = window.atob(data);
+  const size = binString.length;
+  const bytes = new Uint8Array(size);
+  for (let i = 0; i < size; i++) {
+    bytes[i] = binString.charCodeAt(i);
+  }
+  return bytes;
+}