JACOBIN-552 Adding unit tests for cpUtils

src/classloader/cpUtils_test.go

@@ -7,8 +7,11 @@
 package classloader
 
 import (
+ "jacobin/frames"
  "jacobin/globals"
  "jacobin/log"
+ "jacobin/types"
+ "os"
  "testing"
 )
 
@@ -42,3 +45,59 @@ func TestMeInfoFromMethRefInvalid(t *testing.T) {
  t.Errorf("Did not get expected result for pointing to CPentry that's not a MethodRef")
  }
 }
+
+func TestMeInfoFromMethRefValid(t *testing.T) {
+ globals.InitGlobals("test")
+
+ // redirect stderr so as not to pollute the test output with the expected error message
+ normalStderr := os.Stderr
+ _, w, _ := os.Pipe()
+ os.Stderr = w
+
+ // Initialize classloaders and method area
+ err := Init()
+ if err != nil {
+ t.Errorf("Failure to load classes in TestMeInfoFromMethRefValid")
+ }
+ LoadBaseClasses() // must follow classloader.Init()
+
+ f := frames.CreateFrame(4)
+ f.Meth = append(f.Meth, 0x00)
+ f.Meth = append(f.Meth, 0x01) // Go to slot 0x0001 in the CP
+
+ CP := CPool{}
+ CP.CpIndex = make([]CpEntry, 10)
+ CP.CpIndex[0] = CpEntry{Type: 0, Slot: 0}
+ CP.CpIndex[1] = CpEntry{Type: MethodRef, Slot: 0}
+
+ CP.MethodRefs = make([]MethodRefEntry, 1)
+ CP.MethodRefs[0] = MethodRefEntry{ClassIndex: 2, NameAndType: 3}
+
+ CP.CpIndex[2] = CpEntry{Type: ClassRef, Slot: 0}
+ CP.ClassRefs = make([]uint32, 4)
+ CP.ClassRefs[0] = types.ObjectPoolStringIndex
+
+ CP.CpIndex[3] = CpEntry{Type: NameAndType, Slot: 0}
+ CP.NameAndTypes = make([]NameAndTypeEntry, 4)
+ CP.NameAndTypes[0] = NameAndTypeEntry{
+ NameIndex: 4,
+ DescIndex: 5,
+ }
+ CP.CpIndex[4] = CpEntry{Type: UTF8, Slot: 0} // method name
+ CP.Utf8Refs = make([]string, 4)
+ CP.Utf8Refs[0] = "<init>"
+
+ CP.CpIndex[5] = CpEntry{Type: UTF8, Slot: 1} // method name
+ CP.Utf8Refs[1] = "()V"
+
+ f.CP = &CP
+
+ _, s2, s3 := GetMethInfoFromCPmethref(&CP, 1)
+ if s2 != "<init>" && s3 != "()V" {
+ t.Errorf("Expect to get a method: <init>()V, got %s%s", s2, s2)
+ }
+
+ // restore stderr
+ _ = w.Close()
+ os.Stderr = normalStderr
+}