bug fix: ignore private variables when marshaling (#24)

* bug fix: ignore private variables when marshaling

* include coverage in github actions

Author: jbsmith7741

.github/workflows/test.yml

@@ -4,7 +4,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.13.x, 1.14.x, 1.15.x, 1.16.x]
+        go-version: [1.13.x, 1.14.x, 1.15.x, 1.16.x, 1.17.x]
         os: [ubuntu-latest]
     runs-on: ${{ matrix.os }}
     steps:
@@ -15,4 +15,18 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v2
     - name: Test
-      run: go test ./...
+      run: go test ./...
+  coverage:
+    runs-on: ubuntu-latest
+    steps: 
+     - name: Install Go
+       uses: actions/setup-go@v2
+       with: 
+        go-version: 1.18.x
+     - name: Checkout code
+       uses: actions/checkout@v2
+     - name: Test
+       run: | 
+        go test -v -race -coverprofile=coverage.txt -covermode=atomic
+     - name: Coverage 
+       uses: codecov/codecov-action@v2  

marshal.go

@@ -66,7 +66,9 @@ func MarshalUnescaped(v interface{}) string {
 func parseStruct(u *url.URL, uVal *url.Values, vStruct reflect.Value) {
 	for i := 0; i < vStruct.NumField(); i++ {
 		field := vStruct.Field(i)
-
+		if !field.CanInterface() {
+			continue // skip unexported variables
+		}
 		// check for embedded struct and handle recursively
 		if field.Kind() == reflect.Struct {
 			ptr := reflect.New(field.Type())

marshal_test.go

@@ -315,6 +315,13 @@ func TestMarshal(t *testing.T) {
 			}{String: "Fuji"},
 			Expected: "?String=Fuji",
 		},
+		"private": {
+			Input: struct {
+				Int  int
+				name string
+			}{Int: 7, name: "hello"},
+			Expected: "?Int=7",
+		},
 	}
 	trial.New(fn, cases).SubTest(t)
 }