test: Add unit test for priority api

mocks/all_priorities.json

@@ -0,0 +1,42 @@
+[
+  {
+    "self": "https://issues.apache.org/jira/rest/api/2/priority/1",
+    "statusColor": "#cc0000",
+    "description": "Blocks development and/or testing work, production could not run",
+    "iconUrl": "https://issues.apache.org/jira/images/icons/priorities/blocker.svg",
+    "name": "Blocker",
+    "id": "1"
+  },
+  {
+    "self": "https://issues.apache.org/jira/rest/api/2/priority/2",
+    "statusColor": "#ff0000",
+    "description": "Crashes, loss of data, severe memory leak.",
+    "iconUrl": "https://issues.apache.org/jira/images/icons/priorities/critical.svg",
+    "name": "Critical",
+    "id": "2"
+  },
+  {
+    "self": "https://issues.apache.org/jira/rest/api/2/priority/3",
+    "statusColor": "#009900",
+    "description": "Major loss of function.",
+    "iconUrl": "https://issues.apache.org/jira/images/icons/priorities/major.svg",
+    "name": "Major",
+    "id": "3"
+  },
+  {
+    "self": "https://issues.apache.org/jira/rest/api/2/priority/4",
+    "statusColor": "#006600",
+    "description": "Minor loss of function, or other problem where easy workaround is present.",
+    "iconUrl": "https://issues.apache.org/jira/images/icons/priorities/minor.svg",
+    "name": "Minor",
+    "id": "4"
+  },
+  {
+    "self": "https://issues.apache.org/jira/rest/api/2/priority/5",
+    "statusColor": "#003300",
+    "description": "Cosmetic problem like misspelt words or misaligned text.",
+    "iconUrl": "https://issues.apache.org/jira/images/icons/priorities/trivial.svg",
+    "name": "Trivial",
+    "id": "5"
+  }
+]

priority.go

@@ -29,7 +29,7 @@ func (s *PriorityService) GetList() ([]Priority, *Response, error) {
 	}
 
 	priorityList := []Priority{}
-	resp, err := s.client.Do(req, priorityList)
+	resp, err := s.client.Do(req, &priorityList)
 	if err != nil {
 		return nil, resp, NewJiraError(resp, err)
 	}

priority_test.go

@@ -0,0 +1,32 @@
+package jira
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"testing"
+)
+
+func TestPriorityService_GetList(t *testing.T) {
+	setup()
+	defer teardown()
+	testAPIEdpoint := "/rest/api/2/priority"
+
+	raw, err := ioutil.ReadFile("./mocks/all_priorities.json")
+	if err != nil {
+		t.Error(err.Error())
+	}
+	testMux.HandleFunc(testAPIEdpoint, func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+		testRequestURL(t, r, testAPIEdpoint)
+		fmt.Fprint(w, string(raw))
+	})
+
+	priorities, _, err := testClient.Priority.GetList()
+	if priorities == nil {
+		t.Error("Expected priority list. Priority list is nil")
+	}
+	if err != nil {
+		t.Errorf("Error given: %s", err)
+	}
+}