Added aliases to commands

Added:
- break: b
- continue: c
- step: si
- next: n
- print: p

Taken from the gdb command list

Also updated .gitignore to ignore built dlv file in cmd/dlv

.gitignore

@@ -8,3 +8,4 @@ notes.txt
 .tags*
 tags
 .dbg_history
+cmd/dlv/dlv

command/command.go

@@ -17,47 +17,80 @@ import (
 
 type cmdfunc func(proc *proctl.DebuggedProcess, args ...string) error
 
+type command struct {
+	aliases []string
+	helpMsg string
+	cmdFn   cmdfunc
+}
+
+// Returns true if the command string matches one of the aliases for this command
+func (c command) match(cmdstr string) bool {
+	for _, v := range c.aliases {
+		if v == cmdstr {
+			return true
+		}
+	}
+	return false
+}
+
 type Commands struct {
-	cmds map[string]cmdfunc
+	cmds    []command
+	lastCmd cmdfunc
 }
 
 // Returns a Commands struct with default commands defined.
 func DebugCommands() *Commands {
-	cmds := map[string]cmdfunc{
+	c := &Commands{}
-		"help":       help,
+
-		"continue":   cont,
+	c.cmds = []command{
-		"next":       next,
+		command{aliases: []string{"help"}, cmdFn: c.help, helpMsg: "help - Prints the help message."},
-		"break":      breakpoint,
+		command{aliases: []string{"break", "b"}, cmdFn: breakpoint, helpMsg: "break|b - Set break point at the entry point of a function, or at a specific file/line. Example: break foo.go:13"},
-		"step":       step,
+		command{aliases: []string{"continue", "c"}, cmdFn: cont, helpMsg: "continue|c - Run until breakpoint or program termination."},
-		"clear":      clear,
+		command{aliases: []string{"step", "si"}, cmdFn: step, helpMsg: "step|si - Single step through program."},
-		"print":      printVar,
+		command{aliases: []string{"next", "n"}, cmdFn: next, helpMsg: "next|n - Step over to next source line."},
-		"threads":    threads,
+		command{aliases: []string{"threads"}, cmdFn: threads, helpMsg: "threads - Print out info for every traced thread."},
-		"goroutines": goroutines,
+		command{aliases: []string{"clear"}, cmdFn: clear, helpMsg: "clear - Deletes breakpoint."},
-		"":           nullCommand,
+		command{aliases: []string{"goroutines"}, cmdFn: goroutines, helpMsg: "goroutines - Print out info for every goroutine."},
+		command{aliases: []string{"print", "p"}, cmdFn: printVar, helpMsg: "print|p $var - Evaluate a variable."},
+		command{aliases: []string{"exit"}, cmdFn: nullCommand, helpMsg: "exit - Exit the debugger."},
 	}
 
-	return &Commands{cmds}
+	return c
 }
 
 // Register custom commands. Expects cf to be a func of type cmdfunc,
 // returning only an error.
-func (c *Commands) Register(cmdstr string, cf cmdfunc) {
+func (c *Commands) Register(cmdstr string, cf cmdfunc, helpMsg string) {
-	c.cmds[cmdstr] = cf
+	for _, v := range c.cmds {
+		if v.match(cmdstr) {
+			v.cmdFn = cf
+			return
+		}
+	}
+
+	c.cmds = append(c.cmds, command{aliases: []string{cmdstr}, cmdFn: cf, helpMsg: helpMsg})
 }
 
 // Find will look up the command function for the given command input.
 // If it cannot find the command it will defualt to noCmdAvailable().
 // If the command is an empty string it will replay the last command.
 func (c *Commands) Find(cmdstr string) cmdfunc {
-	cmd, ok := c.cmds[cmdstr]
+	// If <enter> use last command, if there was one.
-	if !ok {
+	if cmdstr == "" {
-		return noCmdAvailable
+		if c.lastCmd != nil {
+			return c.lastCmd
+		}
+		return nullCommand
 	}
 
-	// Allow <enter> to replay last command
+	for _, v := range c.cmds {
-	c.cmds[""] = cmd
+		if v.match(cmdstr) {
+			c.lastCmd = v.cmdFn
+			return v.cmdFn
+		}
+	}
 
-	return cmd
+	return noCmdAvailable
 }
 
 func CommandFunc(fn func() error) cmdfunc {
@@ -74,17 +107,11 @@ func nullCommand(p *proctl.DebuggedProcess, ars ...string) error {
 	return nil
 }
 
-func help(p *proctl.DebuggedProcess, ars ...string) error {
+func (c *Commands) help(p *proctl.DebuggedProcess, ars ...string) error {
-	fmt.Println(`The following commands are available:
+	fmt.Println("The following commands are available:")
-    break - Set break point at the entry point of a function, or at a specific file/line. Example: break foo.go:13.
+	for _, cmd := range c.cmds {
-    continue - Run until breakpoint or program termination.
+		fmt.Printf("\t%s\n", cmd.helpMsg)
-    step - Single step through program.
+	}
-    next - Step over to next source line.
-    threads - Print out info for every traced thread.
-    goroutines - Print out info for every goroutine.
-    print $var - Evaluate a variable.
-    exit - Exit the debugger.`)
-
 	return nil
 }
 

command/command_test.go

@@ -9,7 +9,7 @@ import (
 
 func TestCommandDefault(t *testing.T) {
 	var (
-		cmds = Commands{make(map[string]cmdfunc)}
+		cmds = Commands{}
 		cmd  = cmds.Find("non-existant-command")
 	)
 
@@ -25,7 +25,7 @@ func TestCommandDefault(t *testing.T) {
 
 func TestCommandReplay(t *testing.T) {
 	cmds := DebugCommands()
-	cmds.Register("foo", func(p *proctl.DebuggedProcess, args ...string) error { return fmt.Errorf("registered command") })
+	cmds.Register("foo", func(p *proctl.DebuggedProcess, args ...string) error { return fmt.Errorf("registered command") }, "foo command")
 	cmd := cmds.Find("foo")
 
 	err := cmd(nil)