Merge pull request #191 from mattfarina/deepcopy

Add deepCopy and mustDeepCopy functions

dict.go

@@ -1,6 +1,9 @@
 package sprig
 
-import "github.com/imdario/mergo"
+import (
+	"github.com/imdario/mergo"
+	"github.com/mitchellh/copystructure"
+)
 
 func set(d map[string]interface{}, key string, value interface{}) map[string]interface{} {
 	d[key] = value
@@ -123,3 +126,16 @@ func values(dict map[string]interface{}) []interface{} {
 
 	return values
 }
+
+func deepCopy(i interface{}) interface{} {
+	c, err := mustDeepCopy(i)
+	if err != nil {
+		panic("deepCopy error: " + err.Error())
+	}
+
+	return c
+}
+
+func mustDeepCopy(i interface{}) (interface{}, error) {
+	return copystructure.Copy(i)
+}

dict_test.go

@@ -177,7 +177,7 @@ func TestMerge(t *testing.T) {
 		"i": "eye",       // overridden twice
 		"j": "jay",       // overridden and merged
 		"k": map[string]interface{}{
-			"l": true,      // overriden
+			"l": true, // overriden
 		},
 	}
 	assert.Equal(t, expected, dict["dst"])
@@ -222,9 +222,9 @@ func TestMergeOverwrite(t *testing.T) {
 		t.Error(err)
 	}
 	expected := map[string]interface{}{
-		"a": 1,     // key overwritten from src1
-		"b": 2,     // merged from src1
-		"c": 3,     // merged from dst
+		"a": 1, // key overwritten from src1
+		"b": 2, // merged from src1
+		"c": 3, // merged from dst
 		"d": map[string]interface{}{ // deep merge
 			"e": "four",
 			"f": 5,
@@ -233,7 +233,7 @@ func TestMergeOverwrite(t *testing.T) {
 		"h": 10,          // merged from src2
 		"i": "i",         // overwritten twice src2 wins
 		"j": "j",         // overwritten twice src2 wins
-		"k": map[string]interface{} { // deep merge
+		"k": map[string]interface{}{ // deep merge
 			"l": false, // overwritten src1 wins
 		},
 	}
@@ -252,3 +252,31 @@ func TestValues(t *testing.T) {
 		}
 	}
 }
+
+func TestDeepCopy(t *testing.T) {
+	tests := map[string]string{
+		`{{- $d := dict "a" 1 "b" 2 | deepCopy }}{{ values $d | sortAlpha | join "," }}`: "1,2",
+		`{{- $d := dict "a" 1 "b" 2 | deepCopy }}{{ keys $d | sortAlpha | join "," }}`:   "a,b",
+		`{{- $one := dict "foo" (dict "bar" "baz") "qux" true -}}{{ deepCopy $one }}`:    "map[foo:map[bar:baz] qux:true]",
+	}
+
+	for tpl, expect := range tests {
+		if err := runt(tpl, expect); err != nil {
+			t.Error(err)
+		}
+	}
+}
+
+func TestMustDeepCopy(t *testing.T) {
+	tests := map[string]string{
+		`{{- $d := dict "a" 1 "b" 2 | mustDeepCopy }}{{ values $d | sortAlpha | join "," }}`: "1,2",
+		`{{- $d := dict "a" 1 "b" 2 | mustDeepCopy }}{{ keys $d | sortAlpha | join "," }}`:   "a,b",
+		`{{- $one := dict "foo" (dict "bar" "baz") "qux" true -}}{{ mustDeepCopy $one }}`:    "map[foo:map[bar:baz] qux:true]",
+	}
+
+	for tpl, expect := range tests {
+		if err := runt(tpl, expect); err != nil {
+			t.Error(err)
+		}
+	}
+}

docs/dicts.md

@@ -174,6 +174,17 @@ The above returns `list["value1", "value2", "value 3"]`. Note that the `values`
 function gives no guarantees about the result ordering- if you care about this,
 then use `sortAlpha`.
 
+## deepCopy, mustDeepCopy
+
+The `deepCopy` and `mustDeepCopy` functions takes a value and makes a deep copy
+of the value. This includes dicts and other structures. `deepCopy` panics
+when there is a problem while `mustDeepCopy` returns an error to the template
+system when there is an error.
+
+```
+dict "a" 1 "b" 2 | deepCopy
+```
+
 ## A Note on Dict Internals
 
 A `dict` is implemented in Go as a `map[string]interface{}`. Go developers can

docs/index.md

@@ -10,7 +10,7 @@ The Sprig library provides over 70 template functions for Go's template language
 - [Defaults Functions](defaults.md): `default`, `empty`, `coalesce`, `toJson`, `toPrettyJson`, `ternary`
 - [Encoding Functions](encoding.md): `b64enc`, `b64dec`, etc.
 - [Lists and List Functions](lists.md): `list`, `first`, `uniq`, etc.
-- [Dictionaries and Dict Functions](dicts.md): `dict`, `hasKey`, `pluck`, etc.
+- [Dictionaries and Dict Functions](dicts.md): `dict`, `hasKey`, `pluck`, `deepCopy`, etc.
 - [Type Conversion Functions](conversion.md): `atoi`, `int64`, `toString`, etc.
 - [File Path Functions](paths.md): `base`, `dir`, `ext`, `clean`, `isAbs`
 - [Flow Control Functions](flow_control.md): `fail`

functions.go

@@ -94,18 +94,18 @@ var genericMap = map[string]interface{}{
 	"hello": func() string { return "Hello!" },
 
 	// Date functions
-  "ago":              dateAgo,
+	"ago":              dateAgo,
 	"date":             date,
 	"date_in_zone":     dateInZone,
 	"date_modify":      dateModify,
-  "dateInZone":       dateInZone,
+	"dateInZone":       dateInZone,
 	"dateModify":       dateModify,
-  "durationRound":    durationRound,
-  "htmlDate":         htmlDate,
+	"durationRound":    durationRound,
+	"htmlDate":         htmlDate,
 	"htmlDateInZone":   htmlDateInZone,
 	"must_date_modify": mustDateModify,
-  "mustDateModify":   mustDateModify,
-  "mustToDate":       mustToDate,
+	"mustDateModify":   mustDateModify,
+	"mustToDate":       mustToDate,
 	"now":              func() time.Time { return time.Now() },
 	"toDate":           toDate,
 	"unixEpoch":        unixEpoch,
@@ -221,6 +221,8 @@ var genericMap = map[string]interface{}{
 	"mustToJson":       mustToJson,
 	"mustToPrettyJson": mustToPrettyJson,
 	"ternary":          ternary,
+	"deepCopy":         deepCopy,
+	"mustDeepCopy":     mustDeepCopy,
 
 	// Reflection
 	"typeOf":     typeOf,

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/google/uuid v1.1.1
 	github.com/huandu/xstrings v1.2.0
 	github.com/imdario/mergo v0.3.7
+	github.com/mitchellh/copystructure v1.0.0
 	github.com/spf13/cast v1.3.0
 	github.com/stretchr/testify v1.4.0
 	golang.org/x/crypto v0.0.0-20190911031432-227b76d455e7

go.sum

@@ -12,6 +12,10 @@ github.com/huandu/xstrings v1.2.0 h1:yPeWdRnmynF7p+lLYz0H2tthW9lqhMJrQV/U7yy4wX0
 github.com/huandu/xstrings v1.2.0/go.mod h1:DvyZB1rfVYsBIigL8HwpZgxHwXozlTgGqn63UyNX5k4=
 github.com/imdario/mergo v0.3.7 h1:Y+UAYTZ7gDEuOfhxKWy+dvb5dRQ6rJjFSdX2HZY1/gI=
 github.com/imdario/mergo v0.3.7/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJh5FfA=
+github.com/mitchellh/copystructure v1.0.0 h1:Laisrj+bAB6b/yJwB5Bt3ITZhGJdqmxquMKeZ+mmkFQ=
+github.com/mitchellh/copystructure v1.0.0/go.mod h1:SNtv71yrdKgLRyLFxmLdkAbkKEFWgYaq1OVrnRcwhnw=
+github.com/mitchellh/reflectwalk v1.0.0 h1:9D+8oIskB4VJBN5SFlmc27fSlIBZaov1Wpk/IfikLNY=
+github.com/mitchellh/reflectwalk v1.0.0/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx0jmZXqmk4esnw=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/spf13/cast v1.3.0 h1:oget//CVOEoFewqQxwr0Ej5yjygnqGkvggSE/gB35Q8=