perf: optimize helper for skipping whitespace before a match

marko-js · Feb 26, 2022 · 2a98010 · 2a98010
1 parent 879d5a8
commit 2a98010
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Showing 3 changed files with 13 additions and 9 deletions.
diff --git a/src/core/Parser.ts b/src/core/Parser.ts
@@ -398,10 +398,17 @@ export class Parser {
 
   // --------------------------
 
-  lookPastWhitespaceFor(str: string, start = 1) {
-    let ahead = start;
-    while (isWhitespaceCode(this.lookAtCharCodeAhead(ahead))) ahead++;
-    return !!this.lookAheadFor(str, this.pos + ahead);
+  consumeWhitespaceIfBefore(str: string, start = 0) {
+    const { pos, data } = this;
+    let cur = pos + start;
+    while (isWhitespaceCode(data.charCodeAt(cur))) cur++;
+
+    if (this.lookAheadFor(str, cur)) {
+      this.pos = cur;
+      return true;
+    }
+
+    return false;
   }
 
   getPreviousNonWhitespaceCharCode(start = -1) {

diff --git a/src/states/ATTRIBUTE.ts b/src/states/ATTRIBUTE.ts
@@ -99,14 +99,12 @@ export const ATTRIBUTE: StateDefinition<AttrMeta> = {
           end: childPart.end,
         };
 
-        if (this.lookPastWhitespaceFor("{")) {
+        if (this.consumeWhitespaceIfBefore("{")) {
           attr.args = {
             start,
             end,
             value,
           };
-          this.consumeWhitespace();
-          this.rewind(1);
         } else {
           attr.args = true;
           this.emit({

diff --git a/src/states/OPEN_TAG.ts b/src/states/OPEN_TAG.ts
@@ -117,8 +117,7 @@ export const OPEN_TAG: StateDefinition<OpenTagMeta> = {
               end: childPart.end,
             };
 
-            if (this.lookPastWhitespaceFor("{")) {
-              this.consumeWhitespace();
+            if (this.consumeWhitespaceIfBefore("{")) {
               const attr = this.enterState(STATE.ATTRIBUTE);
               attr.start = start;
               attr.args = { start, end, value };