Improve additional error messages in SpEL

This commit picks up where 987d6cc left off.

See gh-36756

Author: sbrannen

spring-expression/src/main/java/org/springframework/expression/spel/ast/OpMultiply.java

@@ -127,9 +127,9 @@ private void checkRepeatedTextSize(String text, int count) {
 			throw new SpelEvaluationException(getStartPosition(),
 					SpelMessage.NEGATIVE_REPEATED_TEXT_COUNT, count);
 		}
-		int result = text.length() * count;
+		long result = (long) text.length() * (long) count;
 		if (result < 0 || result > MAX_REPEATED_TEXT_SIZE) {
-			throw new SpelEvaluationException(getStartPosition(),
+			throw new SpelEvaluationException(getRightOperand().getStartPosition(),
 					SpelMessage.MAX_REPEATED_TEXT_SIZE_EXCEEDED, MAX_REPEATED_TEXT_SIZE);
 		}
 	}

spring-expression/src/main/java/org/springframework/expression/spel/ast/OpPlus.java

@@ -153,16 +153,19 @@ else if (CodeFlow.isIntegerForNumericOp(leftNumber) || CodeFlow.isIntegerForNume
 	}
 
 	private void checkStringLength(String string) {
-		if (string.length() > MAX_CONCATENATED_STRING_LENGTH) {
+		checkStringLength(string.length());
+	}
+
+	private void checkStringLength(int stringLength) {
+		if (stringLength > MAX_CONCATENATED_STRING_LENGTH) {
 			throw new SpelEvaluationException(getStartPosition(),
 					SpelMessage.MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, MAX_CONCATENATED_STRING_LENGTH);
 		}
 	}
 
 	private TypedValue concatenate(String leftString, String rightString) {
-		String result = leftString + rightString;
-		checkStringLength(result);
-		return new TypedValue(result);
+		checkStringLength(leftString.length() + rightString.length());
+		return new TypedValue(leftString + rightString);
 	}
 
 	@Override

spring-expression/src/test/java/org/springframework/expression/spel/OperatorTests.java

@@ -574,21 +574,26 @@ void strings() {
 
 	@Test
 	void stringRepeat() {
-		evaluate("'abc' * 0", "", String.class);
-		evaluate("'abc' * 1", "abc", String.class);
-		evaluate("'abc' * 2", "abcabc", String.class);
+		String EMPTY = "";
+		evaluate("'' * 0", EMPTY, String.class);
+		evaluate("'' * 2", EMPTY, String.class);
+		evaluate("'abc' * 0", EMPTY, String.class);
+
+		evaluate("'Abc' * 1", "Abc", String.class);
+		evaluate("'Abc' * 2", "AbcAbc", String.class);
+		evaluate("'Abc' * 3", "AbcAbcAbc", String.class);
 
 		Expression expr = parser.parseExpression("'a' * 256");
 		assertThat(expr.getValue(context, String.class)).hasSize(256);
 
-		// 4 is the position of the '*' (repeat operator)
-		evaluateAndCheckError("'a' * 257", String.class, MAX_REPEATED_TEXT_SIZE_EXCEEDED, 4);
+		// 6 is the position of the repeatCount
+		evaluateAndCheckError("'a' * 257", String.class, MAX_REPEATED_TEXT_SIZE_EXCEEDED, 6);
 
 		// Integer overflow: 2 * ((Integer.MAX_VALUE / 2) + 1) --> integer overflow
 		int repeatCount = (Integer.MAX_VALUE / 2) + 1;
 		assertThat(2 * repeatCount).isNegative();
-		// 5 is the position of the '*' (repeat operator)
-		evaluateAndCheckError("'ab' * " + repeatCount, String.class, MAX_REPEATED_TEXT_SIZE_EXCEEDED, 5);
+		// 7 is the position of the repeatCount
+		evaluateAndCheckError("'ab' * " + repeatCount, String.class, MAX_REPEATED_TEXT_SIZE_EXCEEDED, 7);
 	}
 
 	@Test
@@ -623,12 +628,19 @@ void stringConcatenation() {
 		assertThat(expr.getValue(context, String.class)).hasSize(maxSize);
 
 		// Text is too big
+		context.setVariable("text1", createString(maxSize));
+		context.setVariable("text2", createString(maxSize));
+		evaluateAndCheckError("#text1 + #text2", String.class, MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, 7);
+
 		context.setVariable("text1", createString(maxSize + 1));
 		evaluateAndCheckError("#text1 + ''", String.class, MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, 7);
 		evaluateAndCheckError("#text1 + true", String.class, MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, 7);
 		evaluateAndCheckError("'' + #text1", String.class, MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, 3);
 		evaluateAndCheckError("true + #text1", String.class, MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, 5);
 
+		context.setVariable("text1", createString(maxSize - 1));
+		evaluateAndCheckError("#text1 + 'YZ'", String.class, MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, 7);
+
 		context.setVariable("text1", createString(maxSize / 2));
 		context.setVariable("text2", createString((maxSize / 2) + 1));
 		evaluateAndCheckError("#text1 + #text2", String.class, MAX_CONCATENATED_STRING_LENGTH_EXCEEDED, 7);