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|
package eval
import (
"reflect"
"testing"
)
func TestLexer_BasicTokens(t *testing.T) {
tests := []struct {
name string
input string
expect []TokenKind
}{
{"integer", "42", []TokenKind{TokInt, TokEOF}},
{"float", "3.14", []TokenKind{TokFloat, TokEOF}},
{"float no leading zero", ".5", []TokenKind{TokFloat, TokEOF}},
{"ident", "foo", []TokenKind{TokIdent, TokEOF}},
{"keyword if", "if", []TokenKind{TokIf, TokEOF}},
{"operators", "1 + 2 * 3", []TokenKind{TokInt, TokPlus, TokInt, TokMul, TokInt, TokEOF}},
{"comparison", "a < b", []TokenKind{TokIdent, TokLT, TokIdent, TokEOF}},
{"update", "a // b", []TokenKind{TokIdent, TokUpdate, TokIdent, TokEOF}},
{"ellipsis", "...", []TokenKind{TokEllipsis, TokEOF}},
{"path", "./foo/bar", []TokenKind{TokPath, TokEOF}},
{"search path", "<nixpkgs>", []TokenKind{TokSearchPath, TokEOF}},
{"empty parens", "()", []TokenKind{TokLParen, TokRParen, TokEOF}},
{"empty braces", "{ }", []TokenKind{TokLBrace, TokRBrace, TokEOF}},
{"empty brackets", "[ ]", []TokenKind{TokLBrack, TokRBrack, TokEOF}},
{"let in", "let x = 1; in x", []TokenKind{TokLet, TokIdent, TokAssign, TokInt, TokSemi, TokIn, TokIdent, TokEOF}},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
lex := NewLexer([]byte(tt.input), "<test>")
var got []TokenKind
for {
tok := lex.Next()
got = append(got, tok.Kind)
if tok.Kind == TokEOF {
break
}
}
if !reflect.DeepEqual(got, tt.expect) {
t.Errorf("tokens mismatch:\n got: %v\n want: %v", got, tt.expect)
}
})
}
}
func TestLexer_Strings(t *testing.T) {
tests := []struct {
name string
input string
expect []TokenKind
}{
{"simple string", `"hello"`, []TokenKind{
TokStringOpen, TokStringPart, TokStringClose, TokEOF,
}},
{"empty string", `""`, []TokenKind{
TokStringOpen, TokStringClose, TokEOF,
}},
{"string with escape", `"a\nb"`, []TokenKind{
TokStringOpen, TokStringPart, TokStringClose, TokEOF,
}},
{"basic interpolation", `"hello ${name} world"`, []TokenKind{
TokStringOpen, TokStringPart, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringPart, TokStringClose, TokEOF,
}},
{"interpolation at start", `"${x}rest"`, []TokenKind{
TokStringOpen, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringPart, TokStringClose, TokEOF,
}},
{"interpolation at end", `"start${x}"`, []TokenKind{
TokStringOpen, TokStringPart, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringClose, TokEOF,
}},
{"multiple interpolations", `"${a} and ${b}"`, []TokenKind{
TokStringOpen, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringPart, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringClose, TokEOF,
}},
{"nested braces in interpolation", `"${{ a = 1; }.a}"`, []TokenKind{
TokStringOpen, TokInterpolStart, TokLBrace, TokIdent, TokAssign, TokInt, TokSemi, TokRBrace, TokDot, TokIdent, TokInterpolEnd, TokStringClose, TokEOF,
}},
{"nested string in interpolation", `"${"inner"}"`, []TokenKind{
TokStringOpen, TokInterpolStart, TokStringOpen, TokStringPart, TokStringClose, TokInterpolEnd, TokStringClose, TokEOF,
}},
{"deeply nested", `"${a + "${b}"}"`, []TokenKind{
TokStringOpen, TokInterpolStart, TokIdent, TokPlus, TokStringOpen, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringClose, TokInterpolEnd, TokStringClose, TokEOF,
}},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
lex := NewLexer([]byte(tt.input), "<test>")
var got []TokenKind
for {
tok := lex.Next()
got = append(got, tok.Kind)
if tok.Kind == TokEOF {
break
}
}
if !reflect.DeepEqual(got, tt.expect) {
t.Errorf("tokens mismatch:\n got: %v\n want: %v", got, tt.expect)
}
})
}
}
func TestLexer_IndStrings(t *testing.T) {
tests := []struct {
name string
input string
expect []TokenKind
}{
{"simple ind string", "''hello''", []TokenKind{
TokIndStringOpen, TokIndStringPart, TokIndStringClose, TokEOF,
}},
{"empty ind string", "''''", []TokenKind{
TokIndStringOpen, TokIndStringClose, TokEOF,
}},
{"ind string interpolation", "''hello ${name} world''", []TokenKind{
TokIndStringOpen, TokIndStringPart, TokInterpolStart, TokIdent, TokInterpolEnd, TokIndStringPart, TokIndStringClose, TokEOF,
}},
{"ind string nested braces", "''${if true then \"a\" else \"b\"}''", []TokenKind{
TokIndStringOpen, TokInterpolStart, TokIf, TokIdent, TokThen, TokStringOpen, TokStringPart, TokStringClose, TokElse, TokStringOpen, TokStringPart, TokStringClose, TokInterpolEnd, TokIndStringClose, TokEOF,
}},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
lex := NewLexer([]byte(tt.input), "<test>")
var got []TokenKind
for {
tok := lex.Next()
got = append(got, tok.Kind)
if tok.Kind == TokEOF {
break
}
}
if !reflect.DeepEqual(got, tt.expect) {
t.Errorf("tokens mismatch:\n got: %v\n want: %v", got, tt.expect)
}
})
}
}
func TestLexer_DynamicAttrName(t *testing.T) {
tests := []struct {
name string
input string
expect []TokenKind
}{
{"dynamic attr bare", `{ ${"x"} = 1; }`, []TokenKind{
TokLBrace, TokInterpolStart, TokStringOpen, TokStringPart, TokStringClose, TokInterpolEnd, TokAssign, TokInt, TokSemi, TokRBrace, TokEOF,
}},
{"string as attr name with interp", `{ "foo${x}" = 1; }`, []TokenKind{
TokLBrace, TokStringOpen, TokStringPart, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringClose, TokAssign, TokInt, TokSemi, TokRBrace, TokEOF,
}},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
lex := NewLexer([]byte(tt.input), "<test>")
var got []TokenKind
for {
tok := lex.Next()
got = append(got, tok.Kind)
if tok.Kind == TokEOF {
break
}
}
if !reflect.DeepEqual(got, tt.expect) {
t.Errorf("tokens mismatch:\n got: %v\n want: %v", got, tt.expect)
}
})
}
}
func TestLexer_StringEscapes(t *testing.T) {
tests := []struct {
name string
input string
expectVal string
}{
{"newline", `"\n"`, "\n"},
{"tab", `"\t"`, "\t"},
{"cr", `"\r"`, "\r"},
{"backslash", `"\\"`, "\\"},
{"quote", `"\""`, "\""},
{"dollar", `"\$"`, "$"},
{"unknown escape drops backslash", `"\a"`, "a"},
{"unknown escape x", `"\x"`, "x"},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
lex := NewLexer([]byte(tt.input), "<test>")
tok := lex.Next() // StringOpen
if tok.Kind != TokStringOpen {
t.Fatalf("expected StringOpen, got %v", tok.Kind)
}
tok = lex.Next() // StringPart
if tok.Kind != TokStringPart {
t.Fatalf("expected StringPart, got %v", tok.Kind)
}
if tok.Val != tt.expectVal {
t.Errorf("escape value mismatch:\n got: %q\n want: %q", tok.Val, tt.expectVal)
}
})
}
}
func TestLexer_InterpolInNormalMode(t *testing.T) {
tests := []struct {
name string
input string
expect []TokenKind
}{
{"dynamic attr in attrset", `{ ${x} = 1; }`, []TokenKind{
TokLBrace, TokInterpolStart, TokIdent, TokInterpolEnd, TokAssign, TokInt, TokSemi, TokRBrace, TokEOF,
}},
{"string interp in attrset value", `{ a = "${x}"; }`, []TokenKind{
TokLBrace, TokIdent, TokAssign, TokStringOpen, TokInterpolStart, TokIdent, TokInterpolEnd, TokStringClose, TokSemi, TokRBrace, TokEOF,
}},
{"attrset inside normal interpolation", `${{ a = 1; }.a}`, []TokenKind{
TokInterpolStart, TokLBrace, TokIdent, TokAssign, TokInt, TokSemi, TokRBrace, TokDot, TokIdent, TokInterpolEnd, TokEOF,
}},
{"function call with interpolation arg", `f ${"hello"}`, []TokenKind{
TokIdent, TokInterpolStart, TokStringOpen, TokStringPart, TokStringClose, TokInterpolEnd, TokEOF,
}},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
lex := NewLexer([]byte(tt.input), "<test>")
var got []TokenKind
for {
tok := lex.Next()
got = append(got, tok.Kind)
if tok.Kind == TokEOF {
break
}
}
if !reflect.DeepEqual(got, tt.expect) {
t.Errorf("tokens mismatch:\n got: %v\n want: %v", got, tt.expect)
}
})
}
}
func TestLexer_EmptyFormals(t *testing.T) {
// { }: body — empty formals followed by colon
input := "{}: 1"
lex := NewLexer([]byte(input), "<test>")
var got []TokenKind
for {
tok := lex.Next()
got = append(got, tok.Kind)
if tok.Kind == TokEOF {
break
}
}
expect := []TokenKind{TokLBrace, TokRBrace, TokColon, TokInt, TokEOF}
if !reflect.DeepEqual(got, expect) {
t.Errorf("tokens mismatch:\n got: %v\n want: %v", got, expect)
}
}
|