Fix type finding bugs and add zero vaule for func

1.  In the main loop to find typeName, it will
    continue find type if a type has been already found,
    which will make empty string overwite it latter,
    so if it is found first time, assuming this is the
    type we want, and break out the loop.
2.  Add support for zero value for func type.
3.  If the type not a builtin type (*ast.Ident),
    assuming it is a composite structure, like
    *ast.StructType.

Signed-off-by: Peng Gao <peng.gao.dut@gmail.com>

cachemap/main.go

@@ -37,6 +37,9 @@ func findInGenDecl(genDecl *ast.GenDecl, valueName string) string {
 				indent, ok := valueSpec.Type.(*ast.Ident)
 				if ok {
 					return indent.Name
+				} else {
+					// For other types like StructType
+					return valueName
 				}
 			}
 		}
@@ -71,7 +74,8 @@ func zeroValue(s string) string {
 		if s[0] == '*' || // Pointer
 			strings.Index(s, "map") == 0 || // map
 			strings.Index(s, "chan") == 0 || // chan
-			strings.Index(s, "[]") == 0 { // slice
+			strings.Index(s, "[]") == 0 || // slice
+			strings.Index(s, "func") == 0 { // func
 			return "nil"
 		}
 		return s + "{}"
@@ -125,11 +129,15 @@ func main() {
 	}
 	packageName := "main"
 	typeName := ""
+FIND:
 	for name, pkg := range pkgs {
 		packageName = name
 		for _, f := range pkg.Files {
 			for _, decl := range f.Decls {
 				typeName = findInDecl(decl, *valueType)
+				if typeName != "" {
+					break FIND
+				}
 			}
 		}
 	}