Instrument comparisons inside comparisons

Author: rillig

instrumenter.go

@@ -559,8 +559,10 @@ func (i *instrumenter) visitExpr(exprPtr *ast.Expr) {
 		if expr.Op.Precedence() == token.EQL.Precedence() {
 			*exprPtr = i.wrap(expr)
 		}
-		// TODO: i.visitExpr(&expr.X)
-		// TODO: i.visitExpr(&expr.Y)
+		if expr.Op != token.LAND && expr.Op != token.LOR {
+			i.visitExpr(&expr.X)
+			i.visitExpr(&expr.Y)
+		}
 
 	case *ast.KeyValueExpr:
 		i.visitExpr(&expr.Key)

testdata/instrumenter/BinaryExpr.go

@@ -55,5 +55,5 @@ func binaryExpr(i int, a bool, b bool) {
 		i >= 34 && i <= 35
 
 	m := map[bool]int{}
-	_ = m[i == 41] == m[i == 42] // TODO: instrument
+	_ = m[i == 41] == m[i == 42]
 }

testdata/instrumenter/BinaryExpr.gobco

@@ -27,7 +27,7 @@ func binaryExpr(i int, a bool, b bool) {
 		gobcoCover(16, gobcoCover(21, i >= 34) && gobcoCover(22, i <= 35))
 
 	m := map[bool]int{}
-	_ = gobcoCover(23, m[i == 41] == m[i == 42])
+	_ = gobcoCover(23, m[gobcoCover(24, i == 41)] == m[gobcoCover(25, i == 42)])
 }
 
 // :15:6: "i > 0"
@@ -54,3 +54,5 @@ func binaryExpr(i int, a bool, b bool) {
 // :55:3: "i >= 34"
 // :55:14: "i <= 35"
 // :58:6: "m[i == 41] == m[i == 42]"
+// :58:8: "i == 41"
+// :58:22: "i == 42"