From 484631782e47ab29c6f89db721acef4c4e0f0b12 Mon Sep 17 00:00:00 2001
From: Leon Mika <lmika@lmika.org>
Date: Fri, 6 Sep 2024 20:55:19 +1000
Subject: [PATCH] issue-1: Added str and int

---
 ucl/builtins.go          | 40 ++++++++++++++++++++++
 ucl/inst.go              |  3 ++
 ucl/objs.go              | 22 +++++++++++--
 ucl/testbuiltins_test.go | 71 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 133 insertions(+), 3 deletions(-)

diff --git a/ucl/builtins.go b/ucl/builtins.go
index ac72f67..333abeb 100644
--- a/ucl/builtins.go
+++ b/ucl/builtins.go
@@ -231,6 +231,46 @@ func objectsLessThan(l, r object) (bool, error) {
 	return false, errors.New("objects are not comparable")
 }
 
+func strBuiltin(ctx context.Context, args invocationArgs) (object, error) {
+	if err := args.expectArgn(1); err != nil {
+		return nil, err
+	}
+
+	if args.args[0] == nil {
+		return strObject(""), nil
+	}
+
+	return strObject(args.args[0].String()), nil
+}
+
+func intBuiltin(ctx context.Context, args invocationArgs) (object, error) {
+	if err := args.expectArgn(1); err != nil {
+		return nil, err
+	}
+
+	if args.args[0] == nil {
+		return intObject(0), nil
+	}
+
+	switch v := args.args[0].(type) {
+	case intObject:
+		return v, nil
+	case strObject:
+		i, err := strconv.Atoi(string(v))
+		if err != nil {
+			return nil, errors.New("cannot convert to int")
+		}
+		return intObject(i), nil
+	case boolObject:
+		if v {
+			return intObject(1), nil
+		}
+		return intObject(0), nil
+	}
+
+	return nil, errors.New("cannot convert to int")
+}
+
 func concatBuiltin(ctx context.Context, args invocationArgs) (object, error) {
 	var sb strings.Builder
 
diff --git a/ucl/inst.go b/ucl/inst.go
index 7f38ee8..3448e77 100644
--- a/ucl/inst.go
+++ b/ucl/inst.go
@@ -67,6 +67,9 @@ func New(opts ...InstOption) *Inst {
 	rootEC.addCmd("lt", invokableFunc(ltBuiltin))
 	rootEC.addCmd("le", invokableFunc(leBuiltin))
 
+	rootEC.addCmd("str", invokableFunc(strBuiltin))
+	rootEC.addCmd("int", invokableFunc(intBuiltin))
+
 	rootEC.addCmd("add", invokableFunc(addBuiltin))
 
 	rootEC.addCmd("cat", invokableFunc(concatBuiltin))
diff --git a/ucl/objs.go b/ucl/objs.go
index 6580c9c..1fa18e0 100644
--- a/ucl/objs.go
+++ b/ucl/objs.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"reflect"
 	"strconv"
+	"strings"
 
 	"github.com/lmika/gopkgs/fp/slices"
 )
@@ -51,7 +52,22 @@ func (s listObject) Index(i int) object {
 type hashObject map[string]object
 
 func (s hashObject) String() string {
-	return fmt.Sprintf("%v", map[string]object(s))
+	if len(s) == 0 {
+		return "[:]"
+	}
+
+	sb := strings.Builder{}
+	sb.WriteString("[")
+	for k, v := range s {
+		if sb.Len() != 1 {
+			sb.WriteString(" ")
+		}
+		sb.WriteString(k)
+		sb.WriteString(":")
+		sb.WriteString(v.String())
+	}
+	sb.WriteString("]")
+	return sb.String()
 }
 
 func (s hashObject) Truthy() bool {
@@ -99,9 +115,9 @@ type boolObject bool
 
 func (b boolObject) String() string {
 	if b {
-		return "(true)"
+		return "true"
 	}
-	return "(false))"
+	return "false"
 }
 
 func (b boolObject) Truthy() bool {
diff --git a/ucl/testbuiltins_test.go b/ucl/testbuiltins_test.go
index e8b6424..76bac93 100644
--- a/ucl/testbuiltins_test.go
+++ b/ucl/testbuiltins_test.go
@@ -1022,3 +1022,74 @@ func TestBuiltins_EqNe(t *testing.T) {
 		})
 	}
 }
+
+func TestBuiltins_Str(t *testing.T) {
+	tests := []struct {
+		desc string
+		expr string
+		want string
+	}{
+		{desc: "str", expr: `str "hello"`, want: "hello"},
+		{desc: "int", expr: `str 123`, want: "123"},
+		{desc: "bool 1", expr: `str (eq 1 1)`, want: "true"},
+		{desc: "bool 2", expr: `str (eq 1 0)`, want: "false"},
+		{desc: "list 1", expr: `str [1 2 3]`, want: "[1 2 3]"},
+		{desc: "list 2", expr: `str []`, want: "[]"},
+		{desc: "dict 1", expr: `str ["hello":"world"]`, want: `[hello:world]`},
+		{desc: "dict 2", expr: `str [:]`, want: "[:]"},
+		{desc: "nil", expr: `str ()`, want: ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.desc, func(t *testing.T) {
+			ctx := context.Background()
+			outW := bytes.NewBuffer(nil)
+
+			inst := New(WithOut(outW), WithTestBuiltin())
+
+			eqRes, err := inst.Eval(ctx, tt.expr)
+			assert.NoError(t, err)
+			assert.Equal(t, tt.want, eqRes)
+		})
+	}
+}
+
+func TestBuiltins_Int(t *testing.T) {
+	tests := []struct {
+		desc    string
+		expr    string
+		want    int
+		wantErr bool
+	}{
+		{desc: "str 1", expr: `int "123"`, want: 123},
+		{desc: "str 2", expr: `int "31452"`, want: 31452},
+		{desc: "str 3", expr: `int "-21"`, want: -21},
+		{desc: "int 1", expr: `int 123`, want: 123},
+		{desc: "int 2", expr: `int -21`, want: -21},
+		{desc: "bool 1", expr: `int (eq 1 1)`, want: 1},
+		{desc: "bool 2", expr: `int (eq 1 0)`, want: 0},
+		{desc: "nil", expr: `int ()`, want: 0},
+
+		{desc: "list 1", expr: `int [1 2 3]`, wantErr: true},
+		{desc: "list 2", expr: `int []`, wantErr: true},
+		{desc: "dict 1", expr: `int ["hello":"world"]`, wantErr: true},
+		{desc: "dict 2", expr: `int [:]`, wantErr: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.desc, func(t *testing.T) {
+			ctx := context.Background()
+			outW := bytes.NewBuffer(nil)
+
+			inst := New(WithOut(outW), WithTestBuiltin())
+
+			eqRes, err := inst.Eval(ctx, tt.expr)
+			if tt.wantErr {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.Equal(t, tt.want, eqRes)
+			}
+		})
+	}
+}