Added a CSV module

cmd/cmsh/main.go

@@ -18,10 +18,12 @@ func main() {
 	defer rl.Close()
 
 	instRepl := repl.New(
-		ucl.WithModule(builtins.OS()),
+		ucl.WithModule(builtins.CSV(nil)),
 		ucl.WithModule(builtins.FS(nil)),
 		ucl.WithModule(builtins.Log(nil)),
+		ucl.WithModule(builtins.OS()),
 		ucl.WithModule(builtins.Strs()),
+		ucl.WithModule(builtins.Time()),
 	)
 	ctx := context.Background()
 

cmd/playwasm/jsiter.go

@@ -25,9 +25,11 @@ func initJS(ctx context.Context) {
 	replInst := repl.New(
 		ucl.WithModule(builtins.Log(nil)),
 		ucl.WithModule(builtins.Strs()),
+		ucl.WithModule(builtins.Time()),
 		ucl.WithOut(ucl.LineHandler(func(line string) {
 			invokeUCLCallback("onOutLine", line)
-		})))
+		})),
+	)
 
 	uclObj["eval"] = js.FuncOf(func(this js.Value, args []js.Value) any {
 		if len(args) != 2 {

ucl/builtins.go

@@ -44,13 +44,13 @@ func echoBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 
 func addBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 	if len(args.args) == 0 {
-		return intObject(0), nil
+		return IntObject(0), nil
 	}
 
 	n := 0
 	for i, a := range args.args {
 		switch t := a.(type) {
-		case intObject:
+		case IntObject:
 			n += int(t)
 		case StringObject:
 			v, err := strconv.Atoi(string(t))
@@ -63,19 +63,19 @@ func addBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 		}
 	}
 
-	return intObject(n), nil
+	return IntObject(n), nil
 }
 
 func subBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 	if len(args.args) == 0 {
-		return intObject(0), nil
+		return IntObject(0), nil
 	}
 
 	n := 0
 	for i, a := range args.args {
 		var p int
 		switch t := a.(type) {
-		case intObject:
+		case IntObject:
 			p = int(t)
 		case StringObject:
 			v, err := strconv.Atoi(string(t))
@@ -93,18 +93,18 @@ func subBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 		}
 	}
 
-	return intObject(n), nil
+	return IntObject(n), nil
 }
 
 func mupBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 	if len(args.args) == 0 {
-		return intObject(1), nil
+		return IntObject(1), nil
 	}
 
 	n := 1
 	for i, a := range args.args {
 		switch t := a.(type) {
-		case intObject:
+		case IntObject:
 			n *= int(t)
 		case StringObject:
 			v, err := strconv.Atoi(string(t))
@@ -117,19 +117,19 @@ func mupBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 		}
 	}
 
-	return intObject(n), nil
+	return IntObject(n), nil
 }
 
 func divBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 	if len(args.args) == 0 {
-		return intObject(1), nil
+		return IntObject(1), nil
 	}
 
 	n := 1
 	for i, a := range args.args {
 		var p int
 		switch t := a.(type) {
-		case intObject:
+		case IntObject:
 			p = int(t)
 		case StringObject:
 			v, err := strconv.Atoi(string(t))
@@ -147,19 +147,19 @@ func divBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 		}
 	}
 
-	return intObject(n), nil
+	return IntObject(n), nil
 }
 
 func modBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 	if len(args.args) == 0 {
-		return intObject(0), nil
+		return IntObject(0), nil
 	}
 
 	n := 0
 	for i, a := range args.args {
 		var p int
 		switch t := a.(type) {
-		case intObject:
+		case IntObject:
 			p = int(t)
 		case StringObject:
 			v, err := strconv.Atoi(string(t))
@@ -177,7 +177,7 @@ func modBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 		}
 	}
 
-	return intObject(n), nil
+	return IntObject(n), nil
 }
 
 func setBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
@@ -323,8 +323,8 @@ func objectsEqual(l, r Object) bool {
 		if rv, ok := r.(StringObject); ok {
 			return lv == rv
 		}
-	case intObject:
+	case IntObject:
-		if rv, ok := r.(intObject); ok {
+		if rv, ok := r.(IntObject); ok {
 			return lv == rv
 		}
 	case boolObject:
@@ -384,8 +384,8 @@ func objectsLessThan(l, r Object) (bool, error) {
 		if rv, ok := r.(StringObject); ok {
 			return lv < rv, nil
 		}
-	case intObject:
+	case IntObject:
-		if rv, ok := r.(intObject); ok {
+		if rv, ok := r.(IntObject); ok {
 			return lv < rv, nil
 		}
 	}
@@ -410,23 +410,23 @@ func intBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 	}
 
 	if args.args[0] == nil {
-		return intObject(0), nil
+		return IntObject(0), nil
 	}
 
 	switch v := args.args[0].(type) {
-	case intObject:
+	case IntObject:
 		return v, nil
 	case StringObject:
 		i, err := strconv.Atoi(string(v))
 		if err != nil {
 			return nil, errors.New("cannot convert to int")
 		}
-		return intObject(i), nil
+		return IntObject(i), nil
 	case boolObject:
 		if v {
-			return intObject(1), nil
+			return IntObject(1), nil
 		}
-		return intObject(0), nil
+		return IntObject(0), nil
 	}
 
 	return nil, errors.New("cannot convert to int")
@@ -465,20 +465,20 @@ func lenBuiltin(ctx context.Context, args invocationArgs) (Object, error) {
 
 	switch v := args.args[0].(type) {
 	case StringObject:
-		return intObject(len(string(v))), nil
+		return IntObject(len(string(v))), nil
 	case Listable:
-		return intObject(v.Len()), nil
+		return IntObject(v.Len()), nil
 	case hashable:
-		return intObject(v.Len()), nil
+		return IntObject(v.Len()), nil
 	}
 
-	return intObject(0), nil
+	return IntObject(0), nil
 }
 
 func indexLookup(ctx context.Context, obj, elem Object) (Object, error) {
 	switch v := obj.(type) {
 	case Listable:
-		intIdx, ok := elem.(intObject)
+		intIdx, ok := elem.(IntObject)
 		if !ok {
 			return nil, nil
 		}
@@ -711,9 +711,9 @@ func (s seqObject) Index(i int) Object {
 		return nil
 	}
 	if s.from > s.to {
-		return intObject(s.from - i)
+		return IntObject(s.from - i)
 	}
-	return intObject(s.from + i)
+	return IntObject(s.from + i)
 }
 
 func seqBuiltin(ctx context.Context, args invocationArgs) (Object, error) {

ucl/builtins/csv.go

@@ -0,0 +1,104 @@
+package builtins
+
+import (
+	"context"
+	"encoding/csv"
+	"errors"
+	"io"
+	"io/fs"
+	"strings"
+	"ucl.lmika.dev/ucl"
+)
+
+type csvHandlers struct {
+	fs fs.FS
+}
+
+func CSV(fs fs.FS) ucl.Module {
+	fsh := csvHandlers{fs: fs}
+
+	return ucl.Module{
+		Name: "csv",
+		Builtins: map[string]ucl.BuiltinHandler{
+			"each-record": fsh.eachRecord,
+		},
+	}
+}
+
+func (h csvHandlers) eachRecord(ctx context.Context, args ucl.CallArgs) (any, error) {
+	var (
+		filename string
+		closure  ucl.Invokable
+	)
+
+	if err := args.Bind(&filename, &closure); err != nil {
+		return nil, err
+	}
+
+	f, err := h.fs.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	cr := csv.NewReader(f)
+
+	header, err := cr.Read()
+	if err != nil {
+		return nil, err
+	}
+	hio := make(headerIndexObject)
+	for i, h := range header {
+		hio[h] = i
+	}
+
+	for {
+		record, err := cr.Read()
+		if errors.Is(err, io.EOF) {
+			break
+		} else if err != nil {
+			return nil, err
+		}
+
+		if _, err := closure.Invoke(ctx, stringSlice(record), hio); err != nil {
+			return nil, err
+		}
+	}
+
+	return nil, nil
+}
+
+type headerIndexObject map[string]int
+
+func (hio headerIndexObject) String() string {
+	strs := make([]string, len(hio))
+	for h, i := range hio {
+		strs[i] = h
+	}
+	return strings.Join(strs, ",")
+}
+
+func (hio headerIndexObject) Truthy() bool {
+	return len(hio) > 0
+}
+
+func (hio headerIndexObject) Len() int {
+	return len(hio)
+}
+
+func (hio headerIndexObject) Value(k string) ucl.Object {
+	v, ok := hio[k]
+	if !ok {
+		return nil
+	}
+	return ucl.IntObject(v)
+}
+
+func (hio headerIndexObject) Each(fn func(k string, v ucl.Object) error) error {
+	for k, v := range hio {
+		if err := fn(k, ucl.IntObject(v)); err != nil {
+			return err
+		}
+	}
+	return nil
+}

ucl/builtins/csv_test.go

@@ -0,0 +1,53 @@
+package builtins_test
+
+import (
+	"bytes"
+	"context"
+	"github.com/stretchr/testify/assert"
+	"strings"
+	"testing"
+	"testing/fstest"
+	"ucl.lmika.dev/ucl"
+	"ucl.lmika.dev/ucl/builtins"
+)
+
+var testCsvFS = fstest.MapFS{
+	"test.csv": &fstest.MapFile{
+		Data: []byte(strings.Join([]string{
+			"wind,dir,bearing",
+			"north,N,0",
+			"south,S,180",
+			"east,E,90",
+			"west,W,270",
+		}, "\n")),
+	},
+}
+
+func TestCSV_ReadRecord(t *testing.T) {
+	tests := []struct {
+		descr   string
+		eval    string
+		wantOut string
+	}{
+		{descr: "read csv 1", eval: `csv:each-record "test.csv" { |r h| echo $r.(0) }`, wantOut: "north\nsouth\neast\nwest\n"},
+		{descr: "read csv 2", eval: `csv:each-record "test.csv" { |r h| echo $r.($h.dir) }`, wantOut: "N\nS\nE\nW\n"},
+		{descr: "read csv 3", eval: `csv:each-record "test.csv" { |r h| echo $r.($h.bearing) "-" $r.($h.dir) }`, wantOut: "0-N\n180-S\n90-E\n270-W\n"},
+		{descr: "read csv 4", eval: `csv:each-record "test.csv" { |r h| echo $h.bearing }`, wantOut: "2\n2\n2\n2\n"},
+		{descr: "read csv 5", eval: `csv:each-record "test.csv" {}`, wantOut: ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.descr, func(t *testing.T) {
+			var bfr bytes.Buffer
+
+			inst := ucl.New(
+				ucl.WithModule(builtins.CSV(testCsvFS)),
+				ucl.WithOut(&bfr),
+			)
+
+			_, err := inst.Eval(context.Background(), tt.eval)
+			assert.NoError(t, err)
+			assert.Equal(t, tt.wantOut, bfr.String())
+		})
+	}
+}

ucl/eval.go

@@ -259,7 +259,7 @@ func (e evaluator) evalLiteral(ctx context.Context, ec *evalCtx, n *astLiteral)
 		}
 		return sval, nil
 	case n.Int != nil:
-		return intObject(*n.Int), nil
+		return IntObject(*n.Int), nil
 	}
 	return nil, errors.New("unhandled literal type")
 }

ucl/objs.go

@@ -102,13 +102,13 @@ func (s StringObject) Truthy() bool {
 	return string(s) != ""
 }
 
-type intObject int
+type IntObject int
 
-func (i intObject) String() string {
+func (i IntObject) String() string {
 	return strconv.Itoa(int(i))
 }
 
-func (i intObject) Truthy() bool {
+func (i IntObject) Truthy() bool {
 	return i != 0
 }
 
@@ -143,7 +143,7 @@ func toGoValue(obj Object) (interface{}, bool) {
 		return nil, true
 	case StringObject:
 		return string(v), true
-	case intObject:
+	case IntObject:
 		return int(v), true
 	case boolObject:
 		return bool(v), true
@@ -191,7 +191,7 @@ func fromGoValue(v any) (Object, error) {
 	case string:
 		return StringObject(t), nil
 	case int:
-		return intObject(t), nil
+		return IntObject(t), nil
 	case bool:
 		return boolObject(t), nil
 	case time.Time:
@@ -362,7 +362,7 @@ func (ia invocationArgs) intArg(i int) (int, error) {
 	}
 
 	switch v := ia.args[i].(type) {
-	case intObject:
+	case IntObject:
 		return int(v), nil
 	default:
 		return 0, errors.New("expected an int arg")

ucl/userbuiltin.go

@@ -129,7 +129,7 @@ func (ca CallArgs) bindArg(v interface{}, arg Object) error {
 		}
 		return nil
 	case *int:
-		if iArg, ok := arg.(intObject); ok {
+		if iArg, ok := arg.(IntObject); ok {
 			*t = int(iArg)
 		} else {
 			return errors.New("invalid arg")
@@ -171,7 +171,7 @@ func canBindArg(v interface{}, arg Object) bool {
 	case *string:
 		return true
 	case *int:
-		_, ok := arg.(intObject)
+		_, ok := arg.(IntObject)
 		return ok
 	}