Added test-coverage for the console output functions

We've not added complete tests for the ADM-3A driver, but we've added enough to prove it works - by allowing output to be redirected we can test it does the right kinda thing.
skx · Jun 19, 2024 · ad91209 · ad91209
1 parent 80f35c3
commit ad91209
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Showing 5 changed files with 168 additions and 35 deletions.
diff --git a/consoleout/console_adm3a.go b/consoleout/console_adm3a.go
@@ -1,6 +1,10 @@
 package consoleout
 
-import "fmt"
+import (
+	"fmt"
+	"io"
+	"os"
+)
 
 // Adm3AOutputDriver holds our state.
 type Adm3AOutputDriver struct {
@@ -13,6 +17,9 @@ type Adm3AOutputDriver struct {
 
 	// y stores the cursor Y
 	y uint8
+
+	// writer is where we send our output
+	writer io.Writer
 }
 
 // GetName returns the name of this driver.
@@ -31,40 +38,40 @@ func (a3a *Adm3AOutputDriver) PutCharacter(c uint8) {
 	case 0:
 		switch c {
 		case 0x07: /* BEL: flash screen */
-			fmt.Printf("\033[?5h\033[?5l")
+			fmt.Fprintf(a3a.writer, "\033[?5h\033[?5l")
 		case 0x7F: /* DEL: echo BS, space, BS */
-			fmt.Printf("\b \b")
+			fmt.Fprintf(a3a.writer, "\b \b")
 		case 0x1A: /* adm3a clear screen */
-			fmt.Printf("\033[H\033[2J")
+			fmt.Fprintf(a3a.writer, "\033[H\033[2J")
 		case 0x0C: /* vt52 clear screen */
-			fmt.Printf("\033[H\033[2J")
+			fmt.Fprintf(a3a.writer, "\033[H\033[2J")
 		case 0x1E: /* adm3a cursor home */
-			fmt.Printf("\033[H")
+			fmt.Fprintf(a3a.writer, "\033[H")
 		case 0x1B:
 			a3a.status = 1 /* esc-prefix */
 		case 1:
 			a3a.status = 2 /* cursor motion prefix */
 		case 2: /* insert line */
-			fmt.Printf("\033[L")
+			fmt.Fprintf(a3a.writer, "\033[L")
 		case 3: /* delete line */
-			fmt.Printf("\033[M")
+			fmt.Fprintf(a3a.writer, "\033[M")
 		case 0x18, 5: /* clear to eol */
-			fmt.Printf("\033[K")
+			fmt.Fprintf(a3a.writer, "\033[K")
 		case 0x12, 0x13:
 			// nop
 		default:
-			fmt.Printf("%c", c)
+			fmt.Fprintf(a3a.writer, "%c", c)
 		}
 	case 1: /* we had an esc-prefix */
 		switch c {
 		case 0x1B:
-			fmt.Printf("%c", c)
+			fmt.Fprintf(a3a.writer, "%c", c)
 		case '=', 'Y':
 			a3a.status = 2
 		case 'E': /* insert line */
-			fmt.Printf("\033[L")
+			fmt.Fprintf(a3a.writer, "\033[L")
 		case 'R': /* delete line */
-			fmt.Printf("\033[M")
+			fmt.Fprintf(a3a.writer, "\033[M")
 		case 'B': /* enable attribute */
 			a3a.status = 4
 		case 'C': /* disable attribute */
@@ -75,58 +82,58 @@ func (a3a *Adm3AOutputDriver) PutCharacter(c uint8) {
 			a3a.status = 8
 		default: /* some true ANSI sequence? */
 			a3a.status = 0
-			fmt.Printf("%c%c", 0x1B, c)
+			fmt.Fprintf(a3a.writer, "%c%c", 0x1B, c)
 		}
 	case 2:
 		a3a.y = c - ' ' + 1
 		a3a.status = 3
 	case 3:
 		a3a.x = c - ' ' + 1
 		a3a.status = 0
-		fmt.Printf("\033[%d;%dH", a3a.y, a3a.x)
+		fmt.Fprintf(a3a.writer, "\033[%d;%dH", a3a.y, a3a.x)
 	case 4: /* <ESC>+B prefix */
 		a3a.status = 0
 		switch c {
 		case '0': /* start reverse video */
-			fmt.Printf("\033[7m")
+			fmt.Fprintf(a3a.writer, "\033[7m")
 		case '1': /* start half intensity */
-			fmt.Printf("\033[1m")
+			fmt.Fprintf(a3a.writer, "\033[1m")
 		case '2': /* start blinking */
-			fmt.Printf("\033[5m")
+			fmt.Fprintf(a3a.writer, "\033[5m")
 		case '3': /* start underlining */
-			fmt.Printf("\033[4m")
+			fmt.Fprintf(a3a.writer, "\033[4m")
 		case '4': /* cursor on */
-			fmt.Printf("\033[?25h")
+			fmt.Fprintf(a3a.writer, "\033[?25h")
 		case '5': /* video mode on */
 			// nop
 		case '6': /* remember cursor position */
-			fmt.Printf("\033[s")
+			fmt.Fprintf(a3a.writer, "\033[s")
 		case '7': /* preserve status line */
 			// nop
 		default:
-			fmt.Printf("%cB%c", 0x1B, c)
+			fmt.Fprintf(a3a.writer, "%cB%c", 0x1B, c)
 		}
 	case 5: /* <ESC>+C prefix */
 		a3a.status = 0
 		switch c {
 		case '0': /* stop reverse video */
-			fmt.Printf("\033[27m")
+			fmt.Fprintf(a3a.writer, "\033[27m")
 		case '1': /* stop half intensity */
-			fmt.Printf("\033[m")
+			fmt.Fprintf(a3a.writer, "\033[m")
 		case '2': /* stop blinking */
-			fmt.Printf("\033[25m")
+			fmt.Fprintf(a3a.writer, "\033[25m")
 		case '3': /* stop underlining */
-			fmt.Printf("\033[24m")
+			fmt.Fprintf(a3a.writer, "\033[24m")
 		case '4': /* cursor off */
-			fmt.Printf("\033[?25l")
+			fmt.Fprintf(a3a.writer, "\033[?25l")
 		case '6': /* restore cursor position */
-			fmt.Printf("\033[u")
+			fmt.Fprintf(a3a.writer, "\033[u")
 		case '5': /* video mode off */
 			// nop
 		case '7': /* don't preserve status line */
 			// nop
 		default:
-			fmt.Printf("%cC%c", 0x1B, c)
+			fmt.Fprintf(a3a.writer, "%cC%c", 0x1B, c)
 		}
 		/* set/clear line/point */
 	case 6:
@@ -141,9 +148,16 @@ func (a3a *Adm3AOutputDriver) PutCharacter(c uint8) {
 
 }
 
+// SetWriter will update the writer.
+func (a3a *Adm3AOutputDriver) SetWriter(w io.Writer) {
+	a3a.writer = w
+}
+
 // init registers our driver, by name.
 func init() {
 	Register("adm-3a", func() ConsoleDriver {
-		return &Adm3AOutputDriver{}
+		return &Adm3AOutputDriver{
+			writer: os.Stdout,
+		}
 	})
 }
diff --git a/consoleout/console_ansi.go b/consoleout/console_ansi.go
@@ -1,9 +1,15 @@
 package consoleout
 
-import "fmt"
+import (
+	"fmt"
+	"io"
+	"os"
+)
 
 // AnsiOutputDriver holds our state.
 type AnsiOutputDriver struct {
+	// writer is where we send our output
+	writer io.Writer
 }
 
 // GetName returns the name of this driver.
@@ -17,12 +23,19 @@ func (ad *AnsiOutputDriver) GetName() string {
 //
 // This is part of the OutputDriver interface.
 func (ad *AnsiOutputDriver) PutCharacter(c uint8) {
-	fmt.Printf("%c", c)
+	fmt.Fprintf(ad.writer, "%c", c)
+}
+
+// SetWriter will update the writer.
+func (ad *AnsiOutputDriver) SetWriter(w io.Writer) {
+	ad.writer = w
 }
 
 // init registers our driver, by name.
 func init() {
 	Register("ansi", func() ConsoleDriver {
-		return &AnsiOutputDriver{}
+		return &AnsiOutputDriver{
+			writer: os.Stdout,
+		}
 	})
 }
diff --git a/consoleout/console_null.go b/consoleout/console_null.go
@@ -0,0 +1,43 @@
+package consoleout
+
+import (
+	"io"
+	"os"
+)
+
+// NullOutputDriver holds our state.
+type NullOutputDriver struct {
+
+	// writer is where we send our output
+	writer io.Writer
+}
+
+// GetName returns the name of this driver.
+//
+// This is part of the OutputDriver interface.
+func (no *NullOutputDriver) GetName() string {
+	return "null"
+}
+
+// PutCharacter writes the specified character to the console,
+// as this is a null-driver nothing happens and instead the output
+// is discarded.
+//
+// This is part of the OutputDriver interface.
+func (n *NullOutputDriver) PutCharacter(c uint8) {
+	// NOTHING HAppens
+}
+
+// SetWriter will update the writer.
+func (n *NullOutputDriver) SetWriter(w io.Writer) {
+	n.writer = w
+}
+
+// init registers our driver, by name.
+func init() {
+	Register("null", func() ConsoleDriver {
+		return &NullOutputDriver{
+			writer: os.Stdout,
+		}
+	})
+}
diff --git a/consoleout/console_test.go b/consoleout/console_test.go
@@ -1,6 +1,9 @@
 package consoleout
 
-import "testing"
+import (
+	"bytes"
+	"testing"
+)
 
 // TestName ensures we can lookup a driver by name
 func TestName(t *testing.T) {
@@ -52,3 +55,57 @@ func TestChangeDriver(t *testing.T) {
 		t.Fatalf("driver changed unexpectedly")
 	}
 }
+
+// TestOutput ensures that our two "real" drivers output, as expected
+func TestOutput(t *testing.T) {
+
+	// Drivers that should produce output
+	valid := []string{"ansi", "adm-3a"}
+
+	for _, nm := range valid {
+
+		d, e := New(nm)
+		if e != nil {
+			t.Fatalf("failed to lookup driver by name %s:%s", nm, e)
+		}
+
+		// ensure we redirect the output
+		tmp := &bytes.Buffer{}
+
+		d.driver.SetWriter(tmp)
+
+		for _, c := range "Steve Kemp" {
+			d.PutCharacter(byte(c))
+		}
+
+		// Test we got the output we expected
+		if tmp.String() != "Steve Kemp" {
+			t.Fatalf("output driver %s produced '%s'", d.GetName(), tmp.String())
+		}
+	}
+
+}
+
+// TestNull ensures nothing is written by the null output driver
+func TestNull(t *testing.T) {
+
+	// Start with a known-good driver
+	null, err := New("null")
+	if err != nil {
+		t.Fatalf("failed to load starting driver %s", err)
+	}
+	if null.GetName() != "null" {
+		t.Fatalf("null driver has the wrong name")
+	}
+
+	// ensure we redirect the output
+	tmp := &bytes.Buffer{}
+
+	null.driver.SetWriter(tmp)
+
+	null.PutCharacter('s')
+
+	if tmp.String() != "" {
+		t.Fatalf("got output, expected none: '%s'", tmp.String())
+	}
+}
diff --git a/consoleout/consoleout.go b/consoleout/consoleout.go
@@ -5,7 +5,10 @@
 // given just a name.
 package consoleout
 
-import "fmt"
+import (
+	"fmt"
+	"io"
+)
 
 // ConsoleDriver is the interface that must be implemented by anything
 // that wishes to be used as a console driver.
@@ -19,6 +22,9 @@ type ConsoleDriver interface {
 
 	// GetName will return the name of the driver.
 	GetName() string
+
+	// SetWriter will update the writer
+	SetWriter(io.Writer)
 }
 
 // This is a map of known-drivers