Fixes #12 - adds mock device, more robust tests

CHANGELOG.md

@@ -1,6 +1,6 @@
 # Changelog
 
-## [0.3.0] - 2017-01-21
+## [0.3.0] - 2018-01-21
 
 ### Changed
 - Sends expected data lines with each OBD command to speed up communication

README.org

@@ -61,7 +61,7 @@ Let's start by looking at some example of how you use the library.
 
 ** Example usage
 
-Note: these examples are performed on Linux. If you are using another platform
+*Note:* these examples are performed on Linux. If you are using another platform
 there should be minimal changes, but they are not documented yet. Go ahead
 and put a :+1: on issue #11 if you think this should be prioritized.
 
@@ -106,7 +106,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)
@@ -124,8 +124,10 @@ func main() {
 }
 #+END_SRC
 
-When I run this executable on my machine with the ELM327 device plugged in
-I get the following result:
+*Note:* These examples uses the function ~NewTestDevice~, which uses a mocked
+ELM327 device. To use a real ELM327 device, you instead use ~NewDevice~. The
+reason why a mocked device is used is because the examples should be runnable
+without using a real device.
 
 #+BEGIN_EXAMPLE
 $ go run example.go
@@ -170,7 +172,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)
@@ -212,7 +214,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)
@@ -267,7 +269,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)
@@ -284,7 +286,7 @@ func main() {
 	allCommands := elmobd.GetSensorCommands()
 	carCommands := supported.FilterSupported(allCommands)
 
-	fmt.Printf("%d of %d commands supported:\n", carCommands, allCommands)
+	fmt.Printf("%d of %d commands supported:\n", len(carCommands), len(allCommands))
 
 	for _, cmd := range carCommands {
 		fmt.Printf("- %s supported\n", cmd.Key())
@@ -306,7 +308,7 @@ structure.
 
 The project uses quarterly milestones to plan upcoming changes. The current
 quarter will focus on improving documentation. To see the details of what
-will be done see the milestone [[https://github.com/rzetterberg/elmobd/milestone/2%5D%5D][2018 Q1]].
+will be done see the milestone [[https://github.com/rzetterberg/elmobd/milestone/2][2018 Q1]].
 
 Changes of the library are tracked in the [[file:CHANGELOG.md][CHANGELOG]].
 

automation.py

@@ -95,8 +95,8 @@ def check(args):
     command(['golint'])
 
 def test(args):
-    logger.info('Running unit tests')
-    command(['go', 'test', './...'])
+    logger.info('Running benchmarks, unit tests and examples')
+    command(['go', 'test', '-bench', '.', './...'])
 
     example_files = glob.glob('./examples/**/*.go', recursive=True)
 

device.go

@@ -167,27 +167,40 @@ func (res *Result) PayloadAsByte() (byte, error) {
 	return uint8(result), nil
 }
 
+// RawResult represents the raw text output of running a raw command,
+// including information used in debugging to show what input caused what
+// error, how long the command took, etc.
+type RawResult interface {
+	Failed() bool
+	GetError() error
+	GetOutputs() []string
+	FormatOverview() string
+}
+
+// RawDevice represent the low level device, which can either be the real
+// implementation or a mock implementation used for testing.
+type RawDevice interface {
+	RunCommand(string) RawResult
+}
+
 // Device represents the connection to a ELM327 device. This is the data type
 // you use to run commands on the connected ELM327 device, see NewDevice for
 // creating a Device and RunOBDCommand for running commands.
 type Device struct {
-	rawDevice   *RawDevice
+	rawDevice   RawDevice
 	outputDebug bool
 }
 
 // NewDevice constructs a Device by initilizing the serial connection and
 // setting the protocol to talk with the car to "automatic".
 func NewDevice(devicePath string, debug bool) (*Device, error) {
-	rawDev, err := NewRawDevice(devicePath)
+	rawDev, err := NewRealDevice(devicePath)
 
 	if err != nil {
 		return nil, err
 	}
 
-	dev := Device{
-		rawDev,
-		debug,
-	}
+	dev := Device{rawDev, debug}
 
 	err = dev.SetAutomaticProtocol()
 
@@ -198,25 +211,34 @@ func NewDevice(devicePath string, debug bool) (*Device, error) {
 	return &dev, nil
 }
 
+// NewTestDevice constructs a Device which is using a mocked RawDevice.
+func NewTestDevice(devicePath string, debug bool) (*Device, error) {
+	dev := Device{&MockDevice{}, debug}
+
+	return &dev, nil
+}
+
 // SetAutomaticProtocol tells the ELM327 device to automatically discover what
 // protocol to talk to the car with. How the protocol is chhosen is something
 // that the ELM327 does internally. If you're interested in how this works you
 // can look in the data sheet linked in the beginning of the package description.
 func (dev *Device) SetAutomaticProtocol() error {
-	res := dev.rawDevice.RunCommand("ATSP0")
+	rawRes := dev.rawDevice.RunCommand("ATSP0")
 
-	if res.Error != nil {
-		return res.Error
+	if rawRes.Failed() {
+		return rawRes.GetError()
 	}
 
 	if dev.outputDebug {
-		fmt.Println(res.FormatOverview())
+		fmt.Println(rawRes.FormatOverview())
 	}
 
-	if res.Outputs[0] != "OK" {
+	outputs := rawRes.GetOutputs()
+
+	if outputs[0] != "OK" {
 		return fmt.Errorf(
 			"Expected OK response, got: %q",
-			res.Outputs[0],
+			outputs[0],
 		)
 	}
 
@@ -226,17 +248,18 @@ func (dev *Device) SetAutomaticProtocol() error {
 // GetVersion gets the version of the connected ELM327 device. The latest
 // version being v2.2.
 func (dev *Device) GetVersion() (string, error) {
-	res := dev.rawDevice.RunCommand("AT@1")
+	rawRes := dev.rawDevice.RunCommand("AT@1")
 
-	if res.Error != nil {
-		return "", res.Error
+	if rawRes.Failed() {
+		return "", rawRes.GetError()
 	}
 
 	if dev.outputDebug {
-		fmt.Println(res.FormatOverview())
+		fmt.Println(rawRes.FormatOverview())
 	}
 
-	version := res.Outputs[0][:]
+	outputs := rawRes.GetOutputs()
+	version := outputs[0][:]
 
 	return strings.Trim(version, " "), nil
 }
@@ -290,17 +313,17 @@ func (dev *Device) CheckSupportedCommands() (*SupportedCommands, error) {
 
 // CheckSupportedPart checks the availability of a range of 32 commands.
 func (dev *Device) CheckSupportedPart(cmd OBDCommand) (OBDCommand, error) {
-	rawResult := dev.rawDevice.RunCommand(cmd.ToCommand())
+	rawRes := dev.rawDevice.RunCommand(cmd.ToCommand())
 
-	if rawResult.Error != nil {
-		return cmd, rawResult.Error
+	if rawRes.Failed() {
+		return cmd, rawRes.GetError()
 	}
 
 	if dev.outputDebug {
-		fmt.Println(rawResult.FormatOverview())
+		fmt.Println(rawRes.FormatOverview())
 	}
 
-	result, err := parseOBDResponse(cmd, rawResult.Outputs)
+	result, err := parseOBDResponse(cmd, rawRes.GetOutputs())
 
 	if err != nil {
 		return cmd, err
@@ -320,17 +343,17 @@ func (dev *Device) CheckSupportedPart(cmd OBDCommand) (OBDCommand, error) {
 // RunOBDCommand runs the given OBDCommand on the connected ELM327 device and
 // populates the OBDCommand with the parsed output from the device.
 func (dev *Device) RunOBDCommand(cmd OBDCommand) (OBDCommand, error) {
-	rawResult := dev.rawDevice.RunCommand(cmd.ToCommand())
+	rawRes := dev.rawDevice.RunCommand(cmd.ToCommand())
 
-	if rawResult.Error != nil {
-		return cmd, rawResult.Error
+	if rawRes.Failed() {
+		return cmd, rawRes.GetError()
 	}
 
 	if dev.outputDebug {
-		fmt.Println(rawResult.FormatOverview())
+		fmt.Println(rawRes.FormatOverview())
 	}
 
-	result, err := parseOBDResponse(cmd, rawResult.Outputs)
+	result, err := parseOBDResponse(cmd, rawRes.GetOutputs())
 
 	if err != nil {
 		return cmd, err
@@ -352,13 +375,13 @@ func (dev *Device) RunManyOBDCommands(commands []OBDCommand) ([]OBDCommand, erro
 	var result []OBDCommand
 
 	for _, cmd := range commands {
-		res, err := dev.RunOBDCommand(cmd)
+		processed, err := dev.RunOBDCommand(cmd)
 
 		if err != nil {
 			return []OBDCommand{}, err
 		}
 
-		result = append(result, res)
+		result = append(result, processed)
 	}
 
 	return result, nil

device_test.go

@@ -1,7 +1,6 @@
 package elmobd
 
 import (
-	"fmt"
 	"testing"
 )
 
@@ -41,14 +40,6 @@ func BenchmarkParseOBDResponse2(b *testing.B) {
  * Tests
  */
 
-func assertEqual(t *testing.T, a interface{}, b interface{}) {
-	if a == b {
-		return
-	}
-
-	t.Fatal(fmt.Sprintf("%v != %v", a, b))
-}
-
 func TestToCommand(t *testing.T) {
 	assertEqual(t, NewPart1Supported().ToCommand(), "01001")
 	assertEqual(t, NewEngineLoad().ToCommand(), "01041")
@@ -174,13 +165,6 @@ func TestParseOBDResponse(t *testing.T) {
 	}
 
 	for _, curr := range scenarios {
-		_, err := parseOBDResponse(
-			curr.command,
-			curr.outputs,
-		)
-
-		if err != nil {
-			t.Error("Failed parsing", err)
-		}
+		assertOBDParseSuccess(t, curr.command, curr.outputs)
 	}
 }

examples/example_1/main.go

@@ -15,7 +15,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)

examples/example_2/main.go

@@ -15,7 +15,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)

examples/example_3/main.go

@@ -15,7 +15,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)

examples/example_4/main.go

@@ -15,7 +15,7 @@ func main() {
 
 	flag.Parse()
 
-	dev, err := elmobd.NewDevice(*serialPath, false)
+	dev, err := elmobd.NewTestDevice(*serialPath, false)
 
 	if err != nil {
 		fmt.Println("Failed to create new device", err)
@@ -32,7 +32,7 @@ func main() {
 	allCommands := elmobd.GetSensorCommands()
 	carCommands := supported.FilterSupported(allCommands)
 
-	fmt.Printf("%d of %d commands supported:\n", carCommands, allCommands)
+	fmt.Printf("%d of %d commands supported:\n", len(carCommands), len(allCommands))
 
 	for _, cmd := range carCommands {
 		fmt.Printf("- %s supported\n", cmd.Key())