prefer positive candidates over negative candidates

RobinMalfait · RobinMalfait · commit fcc81f95739c · 2026-03-19T17:58:58.000+01:00
Right now, when we _know_ that a replacement utility exist, then we use
it immediately. However, if multiple match then we don't really know
what to do so up until now we just bailed.

But the funny part is that `-tracking-wide` and `tracking-tight` result
in the exact same signature.

In this situation, we pick the positive value instead of the negative
value. If at any point, multiple positive utilities exist, we bail
again. So this only covers the above scenario where a negative and
positive utility was present.
diff --git a/packages/tailwindcss/src/canonicalize-candidates.ts b/packages/tailwindcss/src/canonicalize-candidates.ts
@@ -1128,11 +1128,29 @@ function arbitraryUtilities(candidate: Candidate, options: InternalCanonicalizeO
     // Find a corresponding utility for the same signature
     let replacements = utilities.get(targetSignature)
 
-    // Multiple utilities can map to the same signature. Not sure how to migrate
-    // this one so let's just skip it for now.
-    //
-    // TODO: Do we just migrate to the first one?
-    if (replacements.length > 1) return
+    // Multiple utilities can map to the same signature.
+    if (replacements.length > 1) {
+      // Prefer positive values over negative values
+      let maybeReplacement: string | undefined = undefined
+      for (let replacement of replacements) {
+        if (replacement[0] === '-') continue // Skip negative values
+
+        // If multiple non-negative replacements exists then we are unsure
+        // what to do, so let's bail.
+        if (maybeReplacement) return
+
+        // Consider this replacement
+        maybeReplacement = replacement
+      }
+
+      if (maybeReplacement) {
+        for (let replacementCandidate of parseCandidate(designSystem, maybeReplacement)) {
+          yield replacementCandidate
+        }
+      }
+
+      return
+    }
 
     // If we didn't find any replacement utilities, let's try to strip the
     // modifier and find a replacement then. If we do, we can try to re-add the
@@ -1353,11 +1371,29 @@ function bareValueUtilities(candidate: Candidate, options: InternalCanonicalizeO
     // Find a corresponding utility for the same signature
     let replacements = utilities.get(targetSignature)
 
-    // Multiple utilities can map to the same signature. Not sure how to migrate
-    // this one so let's just skip it for now.
-    //
-    // TODO: Do we just migrate to the first one?
-    if (replacements.length > 1) return
+    // Multiple utilities can map to the same signature.
+    if (replacements.length > 1) {
+      // Prefer positive values over negative values
+      let maybeReplacement: string | undefined = undefined
+      for (let replacement of replacements) {
+        if (replacement[0] === '-') continue // Skip negative values
+
+        // If multiple non-negative replacements exists then we are unsure
+        // what to do, so let's bail.
+        if (maybeReplacement) return
+
+        // Consider this replacement
+        maybeReplacement = replacement
+      }
+
+      if (maybeReplacement) {
+        for (let replacementCandidate of parseCandidate(designSystem, maybeReplacement)) {
+          yield replacementCandidate
+        }
+      }
+
+      return
+    }
 
     // If we didn't find any replacement utilities, let's try to strip the
     // modifier and find a replacement then. If we do, we can try to re-add the
