From aed1d5f76271dd8b4082d77a1b42e258d1ad8c86 Mon Sep 17 00:00:00 2001
From: Sam Brannen <104798+sbrannen@users.noreply.github.com>
Date: Tue, 28 May 2024 10:19:15 +0200
Subject: [PATCH] Support compilation of map indexing with primitive in SpEL

Prior to this commit, the Spring Expression Language (SpEL) failed to
compile an expression that indexed into a Map using a primitive literal
(boolean, int, long, float, or double).

This commit adds support for compilation of such expressions by
ensuring that primitive literals are boxed into their corresponding
wrapper types in the compiled bytecode.

Closes gh-32903

(cherry picked from commit e9de426eb5ca14b354073ec35f10fa0cdfeb1791)
---
 .../expression/spel/ast/Indexer.java          |  4 +-
 .../spel/SpelCompilationCoverageTests.java    | 47 +++++++++++++++++++
 2 files changed, 48 insertions(+), 3 deletions(-)

diff --git a/spring-expression/src/main/java/org/springframework/expression/spel/ast/Indexer.java b/spring-expression/src/main/java/org/springframework/expression/spel/ast/Indexer.java
index eabf26682ead..9dc12f91fdd0 100644
--- a/spring-expression/src/main/java/org/springframework/expression/spel/ast/Indexer.java
+++ b/spring-expression/src/main/java/org/springframework/expression/spel/ast/Indexer.java
@@ -283,9 +283,7 @@ else if (this.indexedType == IndexedType.MAP) {
 				mv.visitLdcInsn(mapKeyName);
 			}
 			else {
-				cf.enterCompilationScope();
-				index.generateCode(mv, cf);
-				cf.exitCompilationScope();
+				generateIndexCode(mv, cf, index, Object.class);
 			}
 			mv.visitMethodInsn(
 					INVOKEINTERFACE, "java/util/Map", "get", "(Ljava/lang/Object;)Ljava/lang/Object;", true);
diff --git a/spring-expression/src/test/java/org/springframework/expression/spel/SpelCompilationCoverageTests.java b/spring-expression/src/test/java/org/springframework/expression/spel/SpelCompilationCoverageTests.java
index 2c9772d288a1..6667cc0cc0ce 100644
--- a/spring-expression/src/test/java/org/springframework/expression/spel/SpelCompilationCoverageTests.java
+++ b/spring-expression/src/test/java/org/springframework/expression/spel/SpelCompilationCoverageTests.java
@@ -554,6 +554,53 @@ void indexIntoListUsingIntegerWrapper() {
 			assertThat(getAst().getExitDescriptor()).isEqualTo("Ljava/lang/Object");
 		}
 
+		@Test  // gh-32903
+		void indexIntoMapUsingPrimitiveLiteral() {
+			Map<Object, String> map = Map.of(
+					false, "0",   // BooleanLiteral
+					1, "ABC",     // IntLiteral
+					2L, "XYZ",    // LongLiteral
+					9.99F, "~10", // FloatLiteral
+					3.14159, "PI" // RealLiteral
+				);
+			context.setVariable("map", map);
+
+			// BooleanLiteral
+			expression = parser.parseExpression("#map[false]");
+			assertThat(expression.getValue(context)).isEqualTo("0");
+			assertCanCompile(expression);
+			assertThat(expression.getValue(context)).isEqualTo("0");
+			assertThat(getAst().getExitDescriptor()).isEqualTo("Ljava/lang/Object");
+
+			// IntLiteral
+			expression = parser.parseExpression("#map[1]");
+			assertThat(expression.getValue(context)).isEqualTo("ABC");
+			assertCanCompile(expression);
+			assertThat(expression.getValue(context)).isEqualTo("ABC");
+			assertThat(getAst().getExitDescriptor()).isEqualTo("Ljava/lang/Object");
+
+			// LongLiteral
+			expression = parser.parseExpression("#map[2L]");
+			assertThat(expression.getValue(context)).isEqualTo("XYZ");
+			assertCanCompile(expression);
+			assertThat(expression.getValue(context)).isEqualTo("XYZ");
+			assertThat(getAst().getExitDescriptor()).isEqualTo("Ljava/lang/Object");
+
+			// FloatLiteral
+			expression = parser.parseExpression("#map[9.99F]");
+			assertThat(expression.getValue(context)).isEqualTo("~10");
+			assertCanCompile(expression);
+			assertThat(expression.getValue(context)).isEqualTo("~10");
+			assertThat(getAst().getExitDescriptor()).isEqualTo("Ljava/lang/Object");
+
+			// RealLiteral
+			expression = parser.parseExpression("#map[3.14159]");
+			assertThat(expression.getValue(context)).isEqualTo("PI");
+			assertCanCompile(expression);
+			assertThat(expression.getValue(context)).isEqualTo("PI");
+			assertThat(getAst().getExitDescriptor()).isEqualTo("Ljava/lang/Object");
+		}
+
 		private String stringify(Object object) {
 			Stream<? extends Object> stream;
 			if (object instanceof Collection<?> collection) {