Extract sort function and add unit test

Author: taylor-swanson

internal/fleet/integration_policy_resource.go

@@ -341,17 +341,9 @@ func resourceIntegrationPolicyRead(ctx context.Context, d *schema.ResourceData,
 		}
 	}
 
-	existingInputs, _ := d.Get("input").([]any)
-	inputIDToIndex := make(map[string]int, len(existingInputs))
-	for i, v := range existingInputs {
-		inputData, _ := v.(map[string]any)
-		inputID, _ := inputData["input_id"].(string)
-		inputIDToIndex[inputID] = i
-	}
-
 	newInputs := make([]any, 0, len(pkgPolicy.Inputs))
 	for inputID, input := range pkgPolicy.Inputs {
-		inputMap := map[string]any{
+		inputData := map[string]any{
 			"input_id": inputID,
 			"enabled":  input.Enabled,
 		}
@@ -361,36 +353,21 @@ func resourceIntegrationPolicyRead(ctx context.Context, d *schema.ResourceData,
 			if err != nil {
 				return diag.FromErr(err)
 			}
-			inputMap["streams_json"] = string(data)
+			inputData["streams_json"] = string(data)
 		}
 		if input.Vars != nil {
 			data, err := json.Marshal(*input.Vars)
 			if err != nil {
 				return diag.FromErr(err)
 			}
-			inputMap["vars_json"] = string(data)
+			inputData["vars_json"] = string(data)
 		}
 
-		newInputs = append(newInputs, inputMap)
+		newInputs = append(newInputs, inputData)
 	}
 
-	sort.Slice(newInputs, func(i, j int) bool {
-		iInput, _ := newInputs[i].(map[string]any)
-		iID, _ := iInput["input_id"].(string)
-		iIdx, ok := inputIDToIndex[iID]
-		if !ok {
-			return false
-		}
-
-		jInput, _ := newInputs[j].(map[string]any)
-		jID, _ := jInput["input_id"].(string)
-		jIdx, ok := inputIDToIndex[jID]
-		if !ok {
-			return true
-		}
-
-		return iIdx < jIdx
-	})
+	existingInputs, _ := d.Get("input").([]any)
+	sortInputs(newInputs, existingInputs)
 
 	if err := d.Set("input", newInputs); err != nil {
 		return diag.FromErr(err)
@@ -414,3 +391,34 @@ func resourceIntegrationPolicyDelete(ctx context.Context, d *schema.ResourceData
 
 	return diags
 }
+
+// sortInputs will sort the 'incoming' list of input definitions based on
+// the order of inputs defined in the 'existing' list. Inputs not present in
+// 'existing' will be placed at the end of the list. Inputs are identified by
+// their ID ('input_id'). The 'incoming' slice will be sorted in-place.
+func sortInputs(incoming []any, existing []any) {
+	idToIndex := make(map[string]int, len(existing))
+	for i, v := range existing {
+		inputData, _ := v.(map[string]any)
+		inputID, _ := inputData["input_id"].(string)
+		idToIndex[inputID] = i
+	}
+
+	sort.Slice(incoming, func(i, j int) bool {
+		iInput, _ := incoming[i].(map[string]any)
+		iID, _ := iInput["input_id"].(string)
+		iIdx, ok := idToIndex[iID]
+		if !ok {
+			return false
+		}
+
+		jInput, _ := incoming[j].(map[string]any)
+		jID, _ := jInput["input_id"].(string)
+		jIdx, ok := idToIndex[jID]
+		if !ok {
+			return true
+		}
+
+		return iIdx < jIdx
+	})
+}

internal/fleet/shared_test.go

@@ -0,0 +1,63 @@
+package fleet
+
+import (
+	"testing"
+
+	"github.com./stretchr/testify/require"
+)
+
+func Test_SortInputs(t *testing.T) {
+	t.Run("WithExisting", func(t *testing.T) {
+		existing := []any{
+			map[string]any{"input_id": "A", "enabled": true},
+			map[string]any{"input_id": "B", "enabled": true},
+			map[string]any{"input_id": "C", "enabled": true},
+			map[string]any{"input_id": "D", "enabled": true},
+			map[string]any{"input_id": "E", "enabled": true},
+		}
+
+		incoming := []any{
+			map[string]any{"input_id": "G", "enabled": true},
+			map[string]any{"input_id": "F", "enabled": true},
+			map[string]any{"input_id": "B", "enabled": true},
+			map[string]any{"input_id": "E", "enabled": true},
+			map[string]any{"input_id": "C", "enabled": true},
+		}
+
+		want := []any{
+			map[string]any{"input_id": "B", "enabled": true},
+			map[string]any{"input_id": "C", "enabled": true},
+			map[string]any{"input_id": "E", "enabled": true},
+			map[string]any{"input_id": "G", "enabled": true},
+			map[string]any{"input_id": "F", "enabled": true},
+		}
+
+		sortInputs(incoming, existing)
+
+		require.Equal(t, want, incoming)
+	})
+
+	t.Run("WithEmpty", func(t *testing.T) {
+		var existing []any
+
+		incoming := []any{
+			map[string]any{"input_id": "G", "enabled": true},
+			map[string]any{"input_id": "F", "enabled": true},
+			map[string]any{"input_id": "B", "enabled": true},
+			map[string]any{"input_id": "E", "enabled": true},
+			map[string]any{"input_id": "C", "enabled": true},
+		}
+
+		want := []any{
+			map[string]any{"input_id": "G", "enabled": true},
+			map[string]any{"input_id": "F", "enabled": true},
+			map[string]any{"input_id": "B", "enabled": true},
+			map[string]any{"input_id": "E", "enabled": true},
+			map[string]any{"input_id": "C", "enabled": true},
+		}
+
+		sortInputs(incoming, existing)
+
+		require.Equal(t, want, incoming)
+	})
+}