From 9b2c2a9fc8dcea7c40ec6574c6325dc82f534abd Mon Sep 17 00:00:00 2001
From: ghm <ghm@google.com>
Date: Wed, 27 Mar 2024 05:18:37 -0700
Subject: [PATCH] Yoda conditions: consider static fields which are in
 `SHOUTY_CASE` to be constant.

Motivated by `Boolean.TRUE`, but that seemed a bit special-casey.

PiperOrigin-RevId: 619497318
---
 .../errorprone/bugpatterns/YodaCondition.java | 10 ++++-
 .../bugpatterns/YodaConditionTest.java        | 44 +++++++++++++++++++
 2 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/com/google/errorprone/bugpatterns/YodaCondition.java b/core/src/main/java/com/google/errorprone/bugpatterns/YodaCondition.java
index 6ccfcb2cedb..7a2055d6932 100644
--- a/core/src/main/java/com/google/errorprone/bugpatterns/YodaCondition.java
+++ b/core/src/main/java/com/google/errorprone/bugpatterns/YodaCondition.java
@@ -25,6 +25,7 @@
 import static com.google.errorprone.util.ASTHelpers.getNullnessValue;
 import static com.google.errorprone.util.ASTHelpers.getReceiver;
 import static com.google.errorprone.util.ASTHelpers.getSymbol;
+import static com.google.errorprone.util.ASTHelpers.isStatic;
 import static java.lang.String.format;
 
 import com.google.errorprone.BugPattern;
@@ -41,6 +42,7 @@
 import com.sun.source.tree.Tree;
 import com.sun.tools.javac.code.Symbol.VarSymbol;
 import java.util.Objects;
+import java.util.regex.Pattern;
 
 /** See the summary. */
 @BugPattern(
@@ -119,6 +121,12 @@ private static boolean seemsConstant(Tree tree) {
       return true;
     }
     var symbol = getSymbol(tree);
-    return symbol instanceof VarSymbol && symbol.isEnum();
+    if (!(symbol instanceof VarSymbol)) {
+      return false;
+    }
+    return symbol.isEnum()
+        || (isStatic(symbol) && CONSTANT_CASE.matcher(symbol.getSimpleName().toString()).matches());
   }
+
+  private static final Pattern CONSTANT_CASE = Pattern.compile("[A-Z0-9_]+");
 }
diff --git a/core/src/test/java/com/google/errorprone/bugpatterns/YodaConditionTest.java b/core/src/test/java/com/google/errorprone/bugpatterns/YodaConditionTest.java
index 3a6cc6e4bc8..eaf08537c49 100644
--- a/core/src/test/java/com/google/errorprone/bugpatterns/YodaConditionTest.java
+++ b/core/src/test/java/com/google/errorprone/bugpatterns/YodaConditionTest.java
@@ -53,6 +53,50 @@ public void primitive() {
         .doTest();
   }
 
+  @Test
+  public void boxedBoolean() {
+    refactoring
+        .addInputLines(
+            "Test.java",
+            "class Test {",
+            "  boolean yoda(Boolean a) {",
+            "    return Boolean.TRUE.equals(a);",
+            "  }",
+            "}")
+        .addOutputLines(
+            "Test.java",
+            "import java.util.Objects;",
+            "class Test {",
+            "  boolean yoda(Boolean a) {",
+            "    return Objects.equals(a, Boolean.TRUE);",
+            "  }",
+            "}")
+        .doTest();
+  }
+
+  @Test
+  public void boxedVsUnboxedBoolean() {
+    refactoring
+        .addInputLines(
+            "Test.java",
+            "class Test {",
+            "  boolean yoda(boolean a) {",
+            "    return Boolean.TRUE.equals(a);",
+            "  }",
+            "}")
+        .addOutputLines(
+            "Test.java",
+            "class Test {",
+            "  boolean yoda(boolean a) {",
+            // NOTE: this is a broken fix! We could detect this if it turns out to be an issue in
+            // practice.
+            "    return a.equals(Boolean.TRUE);",
+            "  }",
+            "}")
+        .allowBreakingChanges()
+        .doTest();
+  }
+
   @Test
   public void enums() {
     refactoring