test: chain get cli command

Cover the essential function execution paths, no time for every -as-type
combination.

cli/chain.go

@@ -719,6 +719,8 @@ var ChainGetCmd = &cli.Command{
    - account-state
 `,
 	Action: func(cctx *cli.Context) error {
+		afmt := NewAppFmt(cctx.App)
+
 		api, closer, err := GetFullNodeAPI(cctx)
 		if err != nil {
 			return err
@@ -737,7 +739,7 @@ var ChainGetCmd = &cli.Command{
 
 			p = "/ipfs/" + ts.ParentState().String() + p
 			if cctx.Bool("verbose") {
-				fmt.Println(p)
+				afmt.Println(p)
 			}
 		}
 
@@ -752,7 +754,7 @@ var ChainGetCmd = &cli.Command{
 			if err != nil {
 				return err
 			}
-			fmt.Println(string(b))
+			afmt.Println(string(b))
 			return nil
 		}
 
@@ -794,7 +796,7 @@ var ChainGetCmd = &cli.Command{
 		}
 
 		if cbu == nil {
-			fmt.Printf("%x", raw)
+			afmt.Printf("%x", raw)
 			return nil
 		}
 
@@ -806,7 +808,7 @@ var ChainGetCmd = &cli.Command{
 		if err != nil {
 			return err
 		}
-		fmt.Println(string(b))
+		afmt.Println(string(b))
 		return nil
 	},
 }

cli/chain_test.go

@@ -362,3 +362,89 @@ func TestChainList(t *testing.T) {
 		assert.Contains(t, out, "1:")
 	})
 }
+
+func TestChainGet(t *testing.T) {
+	blk := mock.MkBlock(nil, 0, 0)
+	ts := mock.TipSet(blk)
+	cmd := WithCategory("chain", ChainGetCmd)
+
+	// lotus chain get /ipfs/[cid]/some/path
+
+	// given no -as-type flag & ipfs prefix, should print object as JSON if it's marshalable
+	t.Run("ipfs", func(t *testing.T) {
+		path := fmt.Sprintf("/ipfs/%s", blk.Cid().String())
+
+		app, mockApi, buf, done := NewMockAppWithFullAPI(t, cmd)
+		defer done()
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		gomock.InOrder(
+			mockApi.EXPECT().ChainGetNode(ctx, path).Return(&api.IpldObject{Cid: blk.Cid(), Obj: blk}, nil),
+		)
+
+		err := app.Run([]string{"chain", "get", path})
+		assert.NoError(t, err)
+
+		var out types.BlockHeader
+		err = json.Unmarshal(buf.Bytes(), &out)
+		assert.NoError(t, err)
+		assert.Equal(t, *blk, out)
+	})
+
+	// given no -as-type flag & ipfs prefix, should traverse from head.ParentStateRoot and print JSON if it's marshalable
+	t.Run("pstate", func(t *testing.T) {
+		p1 := "/pstate"
+		p2 := fmt.Sprintf("/ipfs/%s", ts.ParentState().String())
+
+		app, mockApi, buf, done := NewMockAppWithFullAPI(t, cmd)
+		defer done()
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		gomock.InOrder(
+			mockApi.EXPECT().ChainHead(ctx).Return(ts, nil),
+			mockApi.EXPECT().ChainGetNode(ctx, p2).Return(&api.IpldObject{Cid: blk.Cid(), Obj: blk}, nil),
+		)
+
+		err := app.Run([]string{"chain", "get", p1})
+		assert.NoError(t, err)
+
+		var out types.BlockHeader
+		err = json.Unmarshal(buf.Bytes(), &out)
+		assert.NoError(t, err)
+		assert.Equal(t, *blk, out)
+	})
+
+	// given an unknown -as-type value, return an error
+	t.Run("unknown-type", func(t *testing.T) {
+		app, mockApi, _, done := NewMockAppWithFullAPI(t, cmd)
+		defer done()
+
+		path := fmt.Sprintf("/ipfs/%s", blk.Cid().String())
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		gomock.InOrder(
+			mockApi.EXPECT().ChainGetNode(ctx, path).Return(&api.IpldObject{Cid: blk.Cid(), Obj: blk}, nil),
+		)
+
+		err := app.Run([]string{"chain", "get", "-as-type=foo", path})
+		assert.Error(t, err)
+	})
+}
+
+func TestChainBisect(t *testing.T) {}
+
+func TestChainExport(t *testing.T) {}
+
+func TestSlashConsensusFault(t *testing.T) {}
+
+func TestChainGasPrice(t *testing.T) {}
+
+func TestChainDecode(t *testing.T) {}
+
+func TestChainEncode(t *testing.T) {}