From 9d272d5bdaacda53e90e7619d2a15bbf97a91dcb Mon Sep 17 00:00:00 2001
From: Vivek Patel <ervicpatelwork@gmail.com>
Date: Fri, 30 Jul 2021 19:09:05 +0530
Subject: [PATCH] Fixes string expressions int param casting issue in workflow

---
 compose/automation/expr_types_test.go | 70 +++++++++++++++++++++++++++
 pkg/expr/func_str.go                  | 29 +++++++++--
 2 files changed, 95 insertions(+), 4 deletions(-)

diff --git a/compose/automation/expr_types_test.go b/compose/automation/expr_types_test.go
index 0c7f62e4b..53893699d 100644
--- a/compose/automation/expr_types_test.go
+++ b/compose/automation/expr_types_test.go
@@ -476,3 +476,73 @@ func TestIsNil(t *testing.T) {
 		})
 	}
 }
+
+func TestGvalStringFunctionParamsIntCasting(t *testing.T) {
+	var (
+		ctx = context.Background()
+		req = require.New(t)
+
+		scope = &expr.Vars{}
+	)
+
+	t.Run("substring", func(t *testing.T) {
+		eval, err := expr.NewParser().Parse(`substring("foobar", 1, -1)`)
+		req.NoError(err)
+
+		res, err := eval.Eval(ctx, scope)
+		req.NoError(err)
+
+		req.Equal("oobar", res.(string))
+	})
+
+	t.Run("replace", func(t *testing.T) {
+		eval, err := expr.NewParser().Parse(`replace(" foo foo foo", "foo", "bar", 1)`)
+		req.NoError(err)
+
+		res, err := eval.Eval(ctx, scope)
+		req.NoError(err)
+
+		req.Equal(" bar foo foo", res.(string))
+	})
+
+	t.Run("split", func(t *testing.T) {
+		eval, err := expr.NewParser().Parse(`split("foo-bar", "-")`)
+		req.NoError(err)
+
+		res, err := eval.Eval(ctx, scope)
+		req.NoError(err)
+
+		req.Equal([]string{"foo", "bar"}, res.([]string))
+	})
+
+	t.Run("has", func(t *testing.T) {
+		eval, err := expr.NewParser().Parse(`has([1,2], 2)`)
+		req.NoError(err)
+
+		res, err := eval.Eval(ctx, scope)
+		req.NoError(err)
+
+		req.Equal(true, res)
+	})
+
+	t.Run("repeat", func(t *testing.T) {
+		eval, err := expr.NewParser().Parse(`repeat("! ", 3)`)
+		req.NoError(err)
+
+		res, err := eval.Eval(ctx, scope)
+		req.NoError(err)
+
+		req.Equal("! ! ! ", res.(string))
+	})
+
+	t.Run("shorten", func(t *testing.T) {
+		eval, err := expr.NewParser().Parse(`shorten("This is a whole sentence", "word", 4)`)
+		req.NoError(err)
+
+		res, err := eval.Eval(ctx, scope)
+		req.NoError(err)
+
+		req.Equal("This is a whole …", res.(string))
+	})
+
+}
diff --git a/pkg/expr/func_str.go b/pkg/expr/func_str.go
index 050f6ffff..76bede31f 100644
--- a/pkg/expr/func_str.go
+++ b/pkg/expr/func_str.go
@@ -3,6 +3,8 @@ package expr
 import (
 	"errors"
 	"fmt"
+	"github.com/spf13/cast"
+	"reflect"
 	"regexp"
 	"strings"
 
@@ -22,22 +24,41 @@ func StringFunctions() []gval.Language {
 		gval.Function("format", fmt.Sprintf),
 		gval.Function("title", title),
 		gval.Function("untitle", untitle),
-		gval.Function("repeat", strings.Repeat),
-		gval.Function("replace", strings.Replace),
+		gvalFunc("repeat", strings.Repeat),
+		gvalFunc("replace", strings.Replace),
 		gval.Function("isUrl", valid.IsURL),
 		gval.Function("isEmail", valid.IsEmail),
 		gval.Function("split", strings.Split),
 		gval.Function("join", join),
 		gval.Function("hasSubstring", hasSubstring),
-		gval.Function("substring", substring),
+		gvalFunc("substring", substring),
 		gval.Function("hasPrefix", strings.HasPrefix),
 		gval.Function("hasSuffix", strings.HasSuffix),
-		gval.Function("shorten", shorten),
+		gvalFunc("shorten", shorten),
 		gval.Function("camelize", camelize),
 		gval.Function("snakify", snakify),
 	}
 }
 
+// gvalFunc cast any nth number of float64 param to int
+func gvalFunc(name string, fn interface{}) gval.Language {
+	return gval.Function(name, func(params ...interface{}) (out interface{}) {
+		in := make([]reflect.Value, len(params))
+		for i, param := range params {
+			if reflect.TypeOf(param).Kind() == reflect.Float64 {
+				param = cast.ToInt(param)
+			}
+			in[i] = reflect.ValueOf(param)
+		}
+		fun := reflect.ValueOf(fn)
+		res := fun.Call(in)
+		if len(res) > 0 {
+			out = cast.ToString(reflect.ValueOf(res[0]).Interface())
+		}
+		return
+	})
+}
+
 func shortest(f string, aa ...string) string {
 	for _, s := range aa {
 		if len(f) > len(s) {