Add lexer tests

go.mod

@@ -3,6 +3,7 @@ module github.com/elk-language/go-prompt
 go 1.14
 
 require (
+ github.com/google/go-cmp v0.5.9 // indirect
  github.com/mattn/go-colorable v0.1.7
  github.com/mattn/go-runewidth v0.0.9
  github.com/mattn/go-tty v0.0.3

go.sum

@@ -1,3 +1,5 @@
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/mattn/go-colorable v0.1.4/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
 github.com/mattn/go-colorable v0.1.7 h1:bQGKb3vps/j0E9GfJQ03JyhRuxsvdAanXlT9BTw3mdw=
 github.com/mattn/go-colorable v0.1.7/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=

lexer_test.go

@@ -0,0 +1,118 @@
+package prompt
+
+import (
+ "testing"
+
+ "github.com/google/go-cmp/cmp"
+ "github.com/google/go-cmp/cmp/cmpopts"
+)
+
+func TestEagerLexerNext(t *testing.T) {
+ tests := map[string]struct {
+ lexer *EagerLexer
+ want Token
+ ok bool
+ }{
+ "return the first token when at the beginning": {
+ lexer: &EagerLexer{
+ tokens: []Token{
+ &SimpleToken{lexeme: "foo"},
+ &SimpleToken{lexeme: "bar"},
+ },
+ currentIndex: 0,
+ },
+ want: &SimpleToken{lexeme: "foo"},
+ ok: true,
+ },
+ "return the second token": {
+ lexer: &EagerLexer{
+ tokens: []Token{
+ &SimpleToken{lexeme: "foo"},
+ &SimpleToken{lexeme: "bar"},
+ &SimpleToken{lexeme: "baz"},
+ },
+ currentIndex: 1,
+ },
+ want: &SimpleToken{lexeme: "bar"},
+ ok: true,
+ },
+ "return false when at the end": {
+ lexer: &EagerLexer{
+ tokens: []Token{
+ &SimpleToken{lexeme: "foo"},
+ &SimpleToken{lexeme: "bar"},
+ &SimpleToken{lexeme: "baz"},
+ },
+ currentIndex: 3,
+ },
+ want: nil,
+ ok: false,
+ },
+ }
+
+ for name, tc := range tests {
+ t.Run(name, func(t *testing.T) {
+ got, ok := tc.lexer.Next()
+ opts := []cmp.Option{
+ cmp.AllowUnexported(SimpleToken{}, EagerLexer{}),
+ }
+ if diff := cmp.Diff(tc.want, got, opts...); diff != "" {
+ t.Fatalf(diff)
+ }
+ if diff := cmp.Diff(tc.ok, ok, opts...); diff != "" {
+ t.Fatalf(diff)
+ }
+ })
+ }
+}
+
+func charLex(s string) []Token {
+ var result []Token
+ for _, char := range s {
+ result = append(result, NewSimpleToken(0, string(char)))
+ }
+
+ return result
+}
+
+func TestEagerLexerInit(t *testing.T) {
+ tests := map[string]struct {
+ lexer *EagerLexer
+ input string
+ want *EagerLexer
+ }{
+ "reset the lexer's state": {
+ lexer: &EagerLexer{
+ lexFunc: charLex,
+ tokens: []Token{
+ &SimpleToken{lexeme: "foo"},
+ &SimpleToken{lexeme: "bar"},
+ },
+ currentIndex: 2,
+ },
+ input: "foo",
+ want: &EagerLexer{
+ lexFunc: charLex,
+ tokens: []Token{
+ &SimpleToken{lexeme: "f"},
+ &SimpleToken{lexeme: "o"},
+ &SimpleToken{lexeme: "o"},
+ },
+ currentIndex: 0,
+ },
+ },
+ }
+
+ for name, tc := range tests {
+ t.Run(name, func(t *testing.T) {
+ tc.lexer.Init(tc.input)
+ opts := []cmp.Option{
+ cmp.AllowUnexported(SimpleToken{}, EagerLexer{}),
+ cmpopts.IgnoreFields(EagerLexer{}, "lexFunc"),
+ }
+ if diff := cmp.Diff(tc.want, tc.lexer, opts...); diff != "" {
+ t.Fatalf(diff)
+ }
+ })
+ }
+}

render.go

@@ -1,7 +1,6 @@
 package prompt
 
 import (
- "fmt"
  "runtime"
  "strings"
 
@@ -258,7 +257,6 @@ func (r *Render) lex(lexer Lexer, input string) {
  a := strings.SplitAfter(s, token.Lexeme())
  s = strings.TrimPrefix(s, a[0])
 
- fmt.Printf("%#v\n", token)
  r.out.SetColor(token.Color(), r.inputBGColor, false)
  r.out.WriteStr(a[0])
  }