This closes #849, add new function `DeleteComment` for delete comment (#1317)

- Update unit tests for the delete comment
- Add 3 errors function for error messages

1 files changed, 26 insertions, 0 deletions

diff --git a/comment_test.go b/comment_test.go
index 01f1e42..c2d9fe2 100644
--- a/comment_test.go
+++ b/comment_test.go
@@ -46,6 +46,32 @@ func TestAddComments(t *testing.T) {
 	assert.EqualValues(t, len(NewFile().GetComments()), 0)
 }
 
+func TestDeleteComment(t *testing.T) {
+	f, err := prepareTestBook1()
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+
+	assert.NoError(t, f.AddComment("Sheet2", "A40", `{"author":"Excelize: ","text":"This is a comment1."}`))
+	assert.NoError(t, f.AddComment("Sheet2", "A41", `{"author":"Excelize: ","text":"This is a comment2."}`))
+	assert.NoError(t, f.AddComment("Sheet2", "C41", `{"author":"Excelize: ","text":"This is a comment3."}`))
+
+	assert.NoError(t, f.DeleteComment("Sheet2", "A40"))
+
+	assert.EqualValues(t, 2, len(f.GetComments()["Sheet2"]))
+	assert.EqualValues(t, len(NewFile().GetComments()), 0)
+
+	// Test delete all comments in a worksheet
+	assert.NoError(t, f.DeleteComment("Sheet2", "A41"))
+	assert.NoError(t, f.DeleteComment("Sheet2", "C41"))
+	assert.EqualValues(t, 0, len(f.GetComments()["Sheet2"]))
+	// Test delete comment on not exists worksheet
+	assert.EqualError(t, f.DeleteComment("SheetN", "A1"), "sheet SheetN is not exist")
+	// Test delete comment with worksheet part
+	f.Pkg.Delete("xl/worksheets/sheet1.xml")
+	assert.NoError(t, f.DeleteComment("Sheet1", "A22"))
+}
+
 func TestDecodeVMLDrawingReader(t *testing.T) {
 	f := NewFile()
 	path := "xl/drawings/vmlDrawing1.xml"