⚡ Bolt: Optimize diffTests string processing bottleneck

.jules/bolt.md

@@ -8,3 +8,6 @@
 ## 2024-05-24 - Pre-compile RegExp in nested loops
 **Learning:** Instantiating `new RegExp()` inside nested array methods like `.filter` and `.some` creates a severe O(N*M) performance bottleneck, especially when matching two large lists (e.g., documented tests vs. actual test files).
 **Action:** Always pre-compile regular expressions and derived strings into an array of "matcher" objects outside of the loop before iterating, which shifts the instantiation cost from O(N*M) to O(N).
+## 2024-05-24 - Pre-compute properties and use Sets instead of nested multi-pass arrays
+**Learning:** Performing `basename()` calculations inside nested multi-pass array iterations (`.filter()` and `.some()`) generates substantial O(N*M) bottlenecks.
+**Action:** When filtering two lists against each other using comparisons that require calculations (like regex matching or `basename`), pre-compute the target properties for all items, and cross-reference them in a single double `for`-loop utilizing `Set`s to track matches, drastically reducing iterations and redundant string operations.

cli/commands/diff.mjs

@@ -346,10 +346,11 @@ function diffTests(dir, config = {}) {
   if (docTests.size === 0 && codeTests.size === 0) return null;
 
   // Glob-aware matching (documented entries are often patterns or basenames).
-  const codeArr = [...codeTests];
 
   // PERFORMANCE OPTIMIZATION: Pre-compile regular expressions to avoid O(N*M)
-  // instantiation bottlenecks inside the nested .filter and .some loops below.
+  // instantiation bottlenecks. We also pre-compute the basename of code paths
+  // and resolve matches in a single cross-check loop, changing multi-pass array
+  // filtering to O(N + M) complexity and preventing redundant string processing overhead.
   const docMatchers = [...docTests].map(docEntry => {
     const entry = String(docEntry).trim();
     const hasSlash = entry.includes('/');
@@ -363,17 +364,30 @@ function diffTests(dir, config = {}) {
     };
   });
 
-  const matches = (matcher, codeRel) => {
-    const subject = matcher.hasSlash ? codeRel : basename(codeRel);
-    return matcher.rx.test(subject);
-  };
+  const codeItems = [...codeTests].map(c => ({
+    rel: c,
+    base: basename(c)
+  }));
+
+  const matchedDocs = new Set();
+  const matchedCode = new Set();
+
+  for (const matcher of docMatchers) {
+    for (const code of codeItems) {
+      const subject = matcher.hasSlash ? code.rel : code.base;
+      if (matcher.rx.test(subject)) {
+        matchedDocs.add(matcher.original);
+        matchedCode.add(code.rel);
+      }
+    }
+  }
 
   return {
     title: 'Test Files',
     icon: '🧪',
-    onlyInDocs: docMatchers.filter(m => !codeArr.some(c => matches(m, c))).map(m => m.original),
-    onlyInCode: codeArr.filter(c => !docMatchers.some(m => matches(m, c))),
-    matched: docMatchers.filter(m => codeArr.some(c => matches(m, c))).map(m => m.original),
+    onlyInDocs: docMatchers.filter(m => !matchedDocs.has(m.original)).map(m => m.original),
+    onlyInCode: codeItems.filter(c => !matchedCode.has(c.rel)).map(c => c.rel),
+    matched: [...matchedDocs],
   };
 }
 

cli/validators/docs-diff.mjs

@@ -168,10 +168,11 @@ function diffTests(dir, config) {
   // bare basenames or full paths. Treat each documented entry as a glob and
   // match it against code test paths (or basenames when the entry has no slash).
   // Exact-string comparison produced the false "N documented but not found".
-  const codeArr = [...codeTests];
 
   // PERFORMANCE OPTIMIZATION: Pre-compile regular expressions to avoid O(N*M)
-  // instantiation bottlenecks inside the nested .filter and .some loops below.
+  // instantiation bottlenecks. We also pre-compute the basename of code paths
+  // and resolve matches in a single cross-check loop, changing multi-pass array
+  // filtering to O(N + M) complexity and preventing redundant string processing overhead.
   const docMatchers = [...docTests].map(docEntry => {
     const entry = String(docEntry).trim();
     const hasSlash = entry.includes('/');
@@ -188,15 +189,28 @@ function diffTests(dir, config) {
     };
   });
 
-  const matches = (matcher, codeRel) => {
-    const subject = matcher.hasSlash ? codeRel : basename(codeRel);
-    return matcher.rx.test(subject);
-  };
+  const codeItems = [...codeTests].map(c => ({
+    rel: c,
+    base: basename(c)
+  }));
+
+  const matchedDocs = new Set();
+  const matchedCode = new Set();
+
+  for (const matcher of docMatchers) {
+    for (const code of codeItems) {
+      const subject = matcher.hasSlash ? code.rel : code.base;
+      if (matcher.rx.test(subject)) {
+        matchedDocs.add(matcher.original);
+        matchedCode.add(code.rel);
+      }
+    }
+  }
 
   return {
     title: 'Test Files',
-    onlyInDocs: docMatchers.filter(m => !codeArr.some(c => matches(m, c))).map(m => m.original),
-    onlyInCode: codeArr.filter(c => !docMatchers.some(m => matches(m, c))),
+    onlyInDocs: docMatchers.filter(m => !matchedDocs.has(m.original)).map(m => m.original),
+    onlyInCode: codeItems.filter(c => !matchedCode.has(c.rel)).map(c => c.rel),
   };
 }