commit bd716745590916b059e39ec9267ee4d038c00f77
author Laurent Le Brun <laurentlb@google.com> Wed Apr 15 11:05:03 2015 +0000
committer Han-Wen Nienhuys <hanwen@google.com> Wed Apr 15 16:21:31 2015 +0000
tree 79cd7d993d7eab3ad12195c6bf7602f2a7adbb99
parent 2e78d6108289de09fb68d3ebb0adfd7f7f372bb6

Catch modulo by 0 errors

--
MOS_MIGRATED_REVID=91181886

src/main/java/com/google/devtools/build/lib/syntax/BinaryOperatorExpression.java

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/BinaryOperatorExpression.java b/src/main/java/com/google/devtools/build/lib/syntax/BinaryOperatorExpression.java
index aa97af9..ac47b63 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/BinaryOperatorExpression.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/BinaryOperatorExpression.java
@@ -187,6 +187,9 @@
       case PERCENT: {
         // int % int
         if (lval instanceof Integer && rval instanceof Integer) {
+          if (rval.equals(0)) {
+            throw new EvalException(getLocation(), "integer modulo by zero");
+          }
           return ((Integer) lval).intValue() % ((Integer) rval).intValue();
         }
 

src/test/java/com/google/devtools/build/lib/syntax/EvaluationTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/syntax/EvaluationTest.java b/src/test/java/com/google/devtools/build/lib/syntax/EvaluationTest.java
index dc43088..a558805 100644
--- a/src/test/java/com/google/devtools/build/lib/syntax/EvaluationTest.java
+++ b/src/test/java/com/google/devtools/build/lib/syntax/EvaluationTest.java
@@ -248,6 +248,14 @@
   }
 
   @Test
+  public void testModulo() throws Exception {
+    assertThat(eval("6 % 2")).isEqualTo(0);
+    assertThat(eval("6 % 4")).isEqualTo(2);
+    assertThat(eval("3 % 6")).isEqualTo(3);
+    checkEvalError("integer modulo by zero", "5 % 0");
+  }
+
+  @Test
   public void testMult() throws Exception {
     assertEquals(42, eval("6 * 7"));