Merge pull request #12 from posener/improves

Enhance program structure and data structures

12 files changed, 186 insertions, 186 deletions

diff --git a/args.go b/args.go
new file mode 100644
index 0000000..86dd41a
--- /dev/null
+++ b/args.go
@@ -0,0 +1,39 @@
+package complete
+
+// Args describes command line arguments
+type Args struct {
+	All           []string
+	Completed     []string
+	Last          string
+	LastCompleted string
+}
+
+func newArgs(line []string) Args {
+	completed := removeLast(line)
+	return Args{
+		All:           line[1:],
+		Completed:     completed,
+		Last:          last(line),
+		LastCompleted: last(completed),
+	}
+}
+
+func (a Args) from(i int) Args {
+	a.All = a.All[i:]
+	a.Completed = a.Completed[i:]
+	return a
+}
+
+func removeLast(a []string) []string {
+	if len(a) > 0 {
+		return a[:len(a)-1]
+	}
+	return a
+}
+
+func last(args []string) (last string) {
+	if len(args) > 0 {
+		last = args[len(args)-1]
+	}
+	return
+}
diff --git a/command.go b/command.go
index f52d175..80b2f99 100644
--- a/command.go
+++ b/command.go
@@ -3,7 +3,7 @@ package complete
 import "github.com/posener/complete/match"
 
 // Command represents a command line
-// It holds the data that enables auto completion of a given typed command line
+// It holds the data that enables auto completion of command line
 // Command can also be a sub command.
 type Command struct {
 	// Sub is map of sub commands of the current command
@@ -12,88 +12,79 @@ type Command struct {
 	Sub Commands
 
 	// Flags is a map of flags that the command accepts.
-	// The key is the flag name, and the value is it's prediction options.
+	// The key is the flag name, and the value is it's predictions.
 	Flags Flags
 
 	// Args are extra arguments that the command accepts, those who are
 	// given without any flag before.
-	Args Predicate
+	Args Predictor
 }
 
 // Commands is the type of Sub member, it maps a command name to a command struct
 type Commands map[string]Command
 
-// Flags is the type Flags of the Flags member, it maps a flag name to the flag
-// prediction options.
-type Flags map[string]Predicate
+// Flags is the type Flags of the Flags member, it maps a flag name to the flag predictions.
+type Flags map[string]Predictor
 
-// options returns all available complete options for the given command
-// args are all except the last command line arguments relevant to the command
-func (c *Command) options(args []string) (options []match.Matcher, only bool) {
+// Predict returns all possible predictions for args according to the command struct
+func (c *Command) Predict(a Args) (predictions []string) {
+	predictions, _ = c.predict(a)
+	return
+}
+
+func (c *Command) predict(a Args) (options []string, only bool) {
 
-	// remove the first argument, which is the command name
-	args = args[1:]
-	wordCurrent := last(args)
-	wordCompleted := last(removeLast(args))
 	// if wordCompleted has something that needs to follow it,
 	// it is the most relevant completion
-	if predicate, ok := c.Flags[wordCompleted]; ok && predicate != nil {
-		Log("Predicting according to flag %s", wordCurrent)
-		return predicate.predict(wordCurrent), true
+	if predictor, ok := c.Flags[a.LastCompleted]; ok && predictor != nil {
+		Log("Predicting according to flag %s", a.Last)
+		return predictor.Predict(a), true
 	}
 
-	sub, options, only := c.searchSub(args)
+	sub, options, only := c.searchSub(a)
 	if only {
 		return
 	}
 
-	// if no subcommand was entered in any of the args, add the
-	// subcommands as complete options.
+	// if no sub command was found, return a list of the sub commands
 	if sub == "" {
-		options = append(options, c.subCommands()...)
+		options = append(options, c.subCommands(a.Last)...)
 	}
 
 	// add global available complete options
 	for flag := range c.Flags {
-		options = append(options, match.Prefix(flag))
+		if match.Prefix(flag, a.Last) {
+			options = append(options, flag)
+		}
 	}
 
 	// add additional expected argument of the command
-	options = append(options, c.Args.predict(wordCurrent)...)
+	if c.Args != nil {
+		options = append(options, c.Args.Predict(a)...)
+	}
 
 	return
 }
 
 // searchSub searches recursively within sub commands if the sub command appear
 // in the on of the arguments.
-func (c *Command) searchSub(args []string) (sub string, all []match.Matcher, only bool) {
-
-	// search for sub command in all arguments except the last one
-	// because that one might not be completed yet
-	searchArgs := removeLast(args)
-
-	for i, arg := range searchArgs {
+func (c *Command) searchSub(a Args) (sub string, all []string, only bool) {
+	for i, arg := range a.Completed {
 		if cmd, ok := c.Sub[arg]; ok {
 			sub = arg
-			all, only = cmd.options(args[i:])
+			all, only = cmd.predict(a.from(i))
 			return
 		}
 	}
-	return "", nil, false
+	return
 }
 
-// suvCommands returns a list of matchers according to the sub command names
-func (c *Command) subCommands() []match.Matcher {
-	subs := make([]match.Matcher, 0, len(c.Sub))
+// subCommands returns a list of matching sub commands
+func (c *Command) subCommands(last string) (prediction []string) {
 	for sub := range c.Sub {
-		subs = append(subs, match.Prefix(sub))
-	}
-	return subs
-}
-
-func removeLast(a []string) []string {
-	if len(a) > 0 {
-		return a[:len(a)-1]
+		if match.Prefix(sub, last) {
+			prediction = append(prediction, sub)
+		}
 	}
-	return a
+	return
 }
diff --git a/complete.go b/complete.go
index c91bf5f..be0876e 100644
--- a/complete.go
+++ b/complete.go
@@ -41,37 +41,23 @@ func New(name string, command Command) *Complete {
 // returns success if the completion ran or if the cli matched
 // any of the given flags, false otherwise
 func (c *Complete) Run() bool {
-	args, ok := getLine()
+	line, ok := getLine()
 	if !ok {
 		// make sure flags parsed,
 		// in case they were not added in the main program
 		return c.CLI.Run()
 	}
-	Log("Completing args: %s", args)
+	Log("Completing line: %s", line)
 
-	options := complete(c.Command, args)
+	a := newArgs(line)
+
+	options := c.Command.Predict(a)
 
 	Log("Completion: %s", options)
 	output(options)
 	return true
 }
 
-// complete get a command an command line arguments and returns
-// matching completion options
-func complete(c Command, args []string) (matching []string) {
-	options, _ := c.options(args)
-
-	// choose only matching options
-	l := last(args)
-	for _, option := range options {
-		Log("option %T, %s -> %t", option, option, option.Match(l))
-		if option.Match(l) {
-			matching = append(matching, option.String())
-		}
-	}
-	return
-}
-
 func getLine() ([]string, bool) {
 	line := os.Getenv(envComplete)
 	if line == "" {
@@ -80,13 +66,6 @@ func getLine() ([]string, bool) {
 	return strings.Split(line, " "), true
 }
 
-func last(args []string) (last string) {
-	if len(args) > 0 {
-		last = args[len(args)-1]
-	}
-	return
-}
-
 func output(options []string) {
 	Log("")
 	// stdout of program defines the complete options
diff --git a/complete_test.go b/complete_test.go
index 282a2f6..ee5a133 100644
--- a/complete_test.go
+++ b/complete_test.go
@@ -13,20 +13,20 @@ func TestCompleter_Complete(t *testing.T) {
 	c := Command{
 		Sub: map[string]Command{
 			"sub1": {
-				Flags: map[string]Predicate{
+				Flags: map[string]Predictor{
 					"-flag1": PredictAnything,
 					"-flag2": PredictNothing,
 				},
 			},
 			"sub2": {
-				Flags: map[string]Predicate{
+				Flags: map[string]Predictor{
 					"-flag2": PredictNothing,
 					"-flag3": PredictSet("opt1", "opt2", "opt12"),
 				},
-				Args: Predicate(PredictDirs("*")).Or(PredictFiles("*.md")),
+				Args: PredictOr(PredictDirs("*"), PredictFiles("*.md")),
 			},
 		},
-		Flags: map[string]Predicate{
+		Flags: map[string]Predictor{
 			"-h":       PredictNothing,
 			"-global1": PredictAnything,
 			"-o":       PredictFiles("*.txt"),
@@ -174,9 +174,9 @@ func TestCompleter_Complete(t *testing.T) {
 
 			tt.args = "cmd " + tt.args
 			os.Setenv(envComplete, tt.args)
-			args, _ := getLine()
+			line, _ := getLine()
 
-			got := complete(c, args)
+			got := c.Predict(newArgs(line))
 
 			sort.Strings(tt.want)
 			sort.Strings(got)
diff --git a/gocomplete/complete.go b/gocomplete/complete.go
index 75d3672..1575e1b 100644
--- a/gocomplete/complete.go
+++ b/gocomplete/complete.go
@@ -6,9 +6,11 @@ import "github.com/posener/complete"
 var (
 	predictEllipsis = complete.PredictSet("./...")
 
-	goFilesOrPackages = complete.PredictFiles("*.go").
-				Or(complete.PredictDirs("*")).
-				Or(predictEllipsis)
+	goFilesOrPackages = complete.PredictOr(
+		complete.PredictFiles("*.go"),
+		complete.PredictDirs("*"),
+		predictEllipsis,
+	)
 )
 
 func main() {
diff --git a/gocomplete/tests.go b/gocomplete/tests.go
index 40210d4..d2c32e7 100644
--- a/gocomplete/tests.go
+++ b/gocomplete/tests.go
@@ -17,15 +17,16 @@ import (
 // and then all the relevant function names.
 // for test names use prefix of 'Test' or 'Example', and for benchmark
 // test names use 'Benchmark'
-func predictTest(funcPrefix ...string) complete.Predicate {
-	return func(last string) []match.Matcher {
+func predictTest(funcPrefix ...string) complete.Predictor {
+	return complete.PredictFunc(func(a complete.Args) (prediction []string) {
 		tests := testNames(funcPrefix)
-		options := make([]match.Matcher, len(tests))
-		for i := range tests {
-			options[i] = match.Prefix(tests[i])
+		for _, t := range tests {
+			if match.Prefix(t, a.Last) {
+				prediction = append(prediction, t)
+			}
 		}
-		return options
-	}
+		return
+	})
 }
 
 // get all test names in current directory
diff --git a/match/file.go b/match/file.go
index 0b554ce..eee5bec 100644
--- a/match/file.go
+++ b/match/file.go
@@ -1,26 +1,16 @@
 package match
 
-import (
-	"strings"
-)
+import "strings"
 
-// File is a file name Matcher, if the last word can prefix the
-// File path, there is a possible match
-type File string
-
-func (a File) String() string {
-	return string(a)
-}
-
-// Match returns true if prefix's abs path prefixes a's abs path
-func (a File) Match(prefix string) bool {
+// File returns true if prefix can match the file
+func File(file, prefix string) bool {
 
 	// special case for current directory completion
-	if a == "./" && (prefix == "." || prefix == "") {
+	if file == "./" && (prefix == "." || prefix == "") {
 		return true
 	}
 
-	cmp := strings.TrimPrefix(string(a), "./")
+	file = strings.TrimPrefix(file, "./")
 	prefix = strings.TrimPrefix(prefix, "./")
-	return strings.HasPrefix(cmp, prefix)
+	return strings.HasPrefix(file, prefix)
 }
diff --git a/match/match.go b/match/match.go
index ae95549..812fcac 100644
--- a/match/match.go
+++ b/match/match.go
@@ -1,11 +1,6 @@
 package match
 
-import "fmt"
-
-// Matcher matches itself to a string
-// it is used for comparing a given argument to the last typed
-// word, and see if it is a possible auto complete option.
-type Matcher interface {
-	fmt.Stringer
-	Match(prefix string) bool
-}
+// Match matches two strings
+// it is used for comparing a term to the last typed
+// word, the prefix, and see if it is a possible auto complete option.
+type Match func(term, prefix string) bool
diff --git a/match/match_test.go b/match/match_test.go
index d7a851a..b5a0d87 100644
--- a/match/match_test.go
+++ b/match/match_test.go
@@ -1,6 +1,7 @@
 package match
 
 import (
+	"fmt"
 	"os"
 	"testing"
 )
@@ -21,11 +22,13 @@ func TestMatch(t *testing.T) {
 	}
 
 	tests := []struct {
-		m     Matcher
+		m     Match
+		long  string
 		tests []matcherTest
 	}{
 		{
-			m: Prefix("abcd"),
+			m:    Prefix,
+			long: "abcd",
 			tests: []matcherTest{
 				{prefix: "", want: true},
 				{prefix: "ab", want: true},
@@ -33,14 +36,16 @@ func TestMatch(t *testing.T) {
 			},
 		},
 		{
-			m: Prefix(""),
+			m:    Prefix,
+			long: "",
 			tests: []matcherTest{
 				{prefix: "ac", want: false},
 				{prefix: "", want: true},
 			},
 		},
 		{
-			m: File("file.txt"),
+			m:    File,
+			long: "file.txt",
 			tests: []matcherTest{
 				{prefix: "", want: true},
 				{prefix: "f", want: true},
@@ -59,7 +64,8 @@ func TestMatch(t *testing.T) {
 			},
 		},
 		{
-			m: File("./file.txt"),
+			m:    File,
+			long: "./file.txt",
 			tests: []matcherTest{
 				{prefix: "", want: true},
 				{prefix: "f", want: true},
@@ -78,7 +84,8 @@ func TestMatch(t *testing.T) {
 			},
 		},
 		{
-			m: File("/file.txt"),
+			m:    File,
+			long: "/file.txt",
 			tests: []matcherTest{
 				{prefix: "", want: true},
 				{prefix: "f", want: false},
@@ -97,7 +104,8 @@ func TestMatch(t *testing.T) {
 			},
 		},
 		{
-			m: File("./"),
+			m:    File,
+			long: "./",
 			tests: []matcherTest{
 				{prefix: "", want: true},
 				{prefix: ".", want: true},
@@ -109,9 +117,9 @@ func TestMatch(t *testing.T) {
 
 	for _, tt := range tests {
 		for _, ttt := range tt.tests {
-			name := "matcher='" + tt.m.String() + "'&prefix='" + ttt.prefix + "'"
+			name := fmt.Sprintf("matcher=%T&long='%s'&prefix='%s'", tt.m, tt.long, ttt.prefix)
 			t.Run(name, func(t *testing.T) {
-				got := tt.m.Match(ttt.prefix)
+				got := tt.m(tt.long, ttt.prefix)
 				if got != ttt.want {
 					t.Errorf("Failed %s: got = %t, want: %t", name, got, ttt.want)
 				}
diff --git a/match/prefix.go b/match/prefix.go
index d54902d..9a01ba6 100644
--- a/match/prefix.go
+++ b/match/prefix.go
@@ -3,13 +3,7 @@ package match
 import "strings"
 
 // Prefix is a simple Matcher, if the word is it's prefix, there is a match
-type Prefix string
-
-func (a Prefix) String() string {
-	return string(a)
-}
-
 // Match returns true if a has the prefix as prefix
-func (a Prefix) Match(prefix string) bool {
-	return strings.HasPrefix(string(a), prefix)
+func Prefix(long, prefix string) bool {
+	return strings.HasPrefix(long, prefix)
 }
diff --git a/predicate.go b/predict.go
index bb7e8cb..9e1cce9 100644
--- a/predicate.go
+++ b/predict.go
@@ -7,52 +7,66 @@ import (
 	"github.com/posener/complete/match"
 )
 
-// Predicate determines what terms can follow a command or a flag
-// It is used for auto completion, given last - the last word in the already
-// in the command line, what words can complete it.
-type Predicate func(last string) []match.Matcher
+// Predictor implements a predict method, in which given
+// command line arguments returns a list of options it predicts.
+type Predictor interface {
+	Predict(Args) []string
+}
 
-// Or unions two predicate functions, so that the result predicate
+// PredictOr unions two predicate functions, so that the result predicate
 // returns the union of their predication
-func (p Predicate) Or(other Predicate) Predicate {
-	if p == nil {
-		return other
-	}
-	if other == nil {
-		return p
-	}
-	return func(last string) []match.Matcher { return append(p.predict(last), other.predict(last)...) }
+func PredictOr(predictors ...Predictor) Predictor {
+	return PredictFunc(func(a Args) (prediction []string) {
+		for _, p := range predictors {
+			if p == nil {
+				continue
+			}
+			prediction = append(prediction, p.Predict(a)...)
+		}
+		return
+	})
 }
 
-func (p Predicate) predict(last string) []match.Matcher {
+// PredictFunc determines what terms can follow a command or a flag
+// It is used for auto completion, given last - the last word in the already
+// in the command line, what words can complete it.
+type PredictFunc func(Args) []string
+
+// Predict invokes the predict function and implements the Predictor interface
+func (p PredictFunc) Predict(a Args) []string {
 	if p == nil {
 		return nil
 	}
-	return p(last)
+	return p(a)
 }
 
 // PredictNothing does not expect anything after.
-var PredictNothing Predicate
+var PredictNothing Predictor
 
 // PredictAnything expects something, but nothing particular, such as a number
 // or arbitrary name.
-func PredictAnything(last string) []match.Matcher { return nil }
+var PredictAnything = PredictFunc(func(Args) []string { return nil })
 
 // PredictSet expects specific set of terms, given in the options argument.
-func PredictSet(options ...string) Predicate {
-	return func(last string) []match.Matcher {
-		ret := make([]match.Matcher, len(options))
-		for i := range options {
-			ret[i] = match.Prefix(options[i])
+func PredictSet(options ...string) Predictor {
+	return predictSet(options)
+}
+
+type predictSet []string
+
+func (p predictSet) Predict(a Args) (prediction []string) {
+	for _, m := range p {
+		if match.Prefix(m, a.Last) {
+			prediction = append(prediction, m)
 		}
-		return ret
 	}
+	return
 }
 
 // PredictDirs will search for directories in the given started to be typed
 // path, if no path was started to be typed, it will complete to directories
 // in the current working directory.
-func PredictDirs(pattern string) Predicate {
+func PredictDirs(pattern string) Predictor {
 	return files(pattern, true, false)
 }
 
@@ -60,19 +74,19 @@ func PredictDirs(pattern string) Predicate {
 // be typed path, if no path was started to be typed, it will complete to files that
 // match the pattern in the current working directory.
 // To match any file, use "*" as pattern. To match go files use "*.go", and so on.
-func PredictFiles(pattern string) Predicate {
+func PredictFiles(pattern string) Predictor {
 	return files(pattern, false, true)
 }
 
-// PredictFilesOrDirs predict any file or directory that matches the pattern
-func PredictFilesOrDirs(pattern string) Predicate {
+// PredictFilesOrDirs any file or directory that matches the pattern
+func PredictFilesOrDirs(pattern string) Predictor {
 	return files(pattern, true, true)
 }
 
-func files(pattern string, allowDirs, allowFiles bool) Predicate {
-	return func(last string) []match.Matcher {
-		dir := dirFromLast(last)
-		Log("looking for files in %s (last=%s)", dir, last)
+func files(pattern string, allowDirs, allowFiles bool) PredictFunc {
+	return func(a Args) (prediction []string) {
+		dir := dirFromLast(a.Last)
+		Log("looking for files in %s (last=%s)", dir, a.Last)
 		files, err := filepath.Glob(filepath.Join(dir, pattern))
 		if err != nil {
 			Log("failed glob operation with pattern '%s': %s", pattern, err)
@@ -84,7 +98,13 @@ func files(pattern string, allowDirs, allowFiles bool) Predicate {
 		if !filepath.IsAbs(pattern) {
 			filesToRel(files)
 		}
-		return filesToMatchers(files)
+		// add all matching files to prediction
+		for _, f := range files {
+			if match.File(f, a.Last) {
+				prediction = append(prediction, f)
+			}
+		}
+		return
 	}
 }
 
@@ -130,14 +150,6 @@ func filesToRel(files []string) {
 	return
 }
 
-func filesToMatchers(files []string) []match.Matcher {
-	options := make([]match.Matcher, len(files))
-	for i, f := range files {
-		options[i] = match.File(f)
-	}
-	return options
-}
-
 // dirFromLast gives the directory of the current written
 // last argument if it represents a file name being written.
 // in case that it is not, we fall back to the current directory.
diff --git a/predicate_test.go b/predict_test.go
index 1a694a1..6b77fbe 100644
--- a/predicate_test.go
+++ b/predict_test.go
@@ -12,7 +12,7 @@ func TestPredicate(t *testing.T) {
 
 	tests := []struct {
 		name string
-		p    Predicate
+		p    Predictor
 		arg  string
 		want []string
 	}{
@@ -38,28 +38,23 @@ func TestPredicate(t *testing.T) {
 			want: []string{},
 		},
 		{
-			name: "nothing",
-			p:    PredictNothing,
-			want: []string{},
-		},
-		{
 			name: "or: word with nil",
-			p:    PredictSet("a").Or(PredictNothing),
+			p:    PredictOr(PredictSet("a"), nil),
 			want: []string{"a"},
 		},
 		{
 			name: "or: nil with word",
-			p:    PredictNothing.Or(PredictSet("a")),
+			p:    PredictOr(nil, PredictSet("a")),
 			want: []string{"a"},
 		},
 		{
 			name: "or: nil with nil",
-			p:    PredictNothing.Or(PredictNothing),
+			p:    PredictOr(PredictNothing, PredictNothing),
 			want: []string{},
 		},
 		{
 			name: "or: word with word with word",
-			p:    PredictSet("a").Or(PredictSet("b")).Or(PredictSet("c")),
+			p:    PredictOr(PredictSet("a"), PredictSet("b"), PredictSet("c")),
 			want: []string{"a", "b", "c"},
 		},
 		{
@@ -118,18 +113,12 @@ func TestPredicate(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name+"?arg='"+tt.arg+"'", func(t *testing.T) {
 
-			matchers := tt.p.predict(tt.arg)
+			matches := tt.p.Predict(newArgs(strings.Split(tt.arg, " ")))
 
-			matchersString := []string{}
-			for _, m := range matchers {
-				if m.Match(tt.arg) {
-					matchersString = append(matchersString, m.String())
-				}
-			}
-			sort.Strings(matchersString)
+			sort.Strings(matches)
 			sort.Strings(tt.want)
 
-			got := strings.Join(matchersString, ",")
+			got := strings.Join(matches, ",")
 			want := strings.Join(tt.want, ",")
 
 			if got != want {