chore(templater): migrate the template engine from slim-sprig to sprout

CHANGELOG.md

@@ -36,6 +36,14 @@
 - Fixed the JSON schema rejecting more keys the Taskfile parser accepts:
   `ignore_error` on a `task:` call, and `if`, `set` and `shopt` on a command
   inside a `for` loop (#2967 by @vmaerten).
+- Migrated the templating engine from `slim-sprig` to
+  [sprout](https://docs.atom.codes/sprout). Every function name Task exposed
+  still resolves, and the ten functions whose argument order changed accept both
+  the old and the new form, reporting the old one under `--verbose`. Some
+  long-standing sprig bugs are fixed as a result, and functions that used to
+  swallow errors now report them — see
+  [Migrating from slim-sprig](https://taskfile.dev/docs/reference/templating#migrating-from-slim-sprig)
+  (#1638, #2006 by @42atomys, by @vmaerten).
 
 ## v3.52.0 - 2026-07-02
 

go.mod

@@ -15,7 +15,7 @@ require (
 	github.com/elliotchance/orderedmap/v3 v3.1.1
 	github.com/fatih/color v1.19.0
 	github.com/fsnotify/fsnotify v1.10.1
-	github.com/go-task/slim-sprig/v3 v3.0.0
+	github.com/go-sprout/sprout v1.0.3
 	github.com/go-task/template v0.2.0
 	github.com/google/uuid v1.6.0
 	github.com/hashicorp/go-getter v1.8.6
@@ -43,6 +43,7 @@ require (
 	cloud.google.com/go/iam v1.13.0 // indirect
 	cloud.google.com/go/monitoring v1.30.0 // indirect
 	cloud.google.com/go/storage v1.64.0 // indirect
+	dario.cat/mergo v1.0.2 // indirect
 	github.com/GoogleCloudPlatform/opentelemetry-operations-go/detectors/gcp v1.35.0 // indirect
 	github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/metric v0.59.0 // indirect
 	github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/resourcemapping v0.59.0 // indirect
@@ -97,13 +98,16 @@ require (
 	github.com/mattn/go-colorable v0.1.15 // indirect
 	github.com/mattn/go-isatty v0.0.24 // indirect
 	github.com/mattn/go-runewidth v0.0.27 // indirect
+	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
+	github.com/mitchellh/reflectwalk v1.0.2 // indirect
 	github.com/muesli/cancelreader v0.2.2 // indirect
 	github.com/pierrec/lz4/v4 v4.1.27 // indirect
 	github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
 	github.com/sergi/go-diff v1.4.0 // indirect
+	github.com/spf13/cast v1.10.0 // indirect
 	github.com/spiffe/go-spiffe/v2 v2.8.1 // indirect
 	github.com/stretchr/objx v0.5.3 // indirect
 	github.com/u-root/u-root v0.16.0 // indirect

go.sum

@@ -26,6 +26,8 @@ cloud.google.com/go/storage v1.64.0 h1:KLpxI/oX9LxeRsNqn877d2WyeT3ryiEwnGt8pwcSP
 cloud.google.com/go/storage v1.64.0/go.mod h1:lWyAtwvDZHdL3k68WVKbESP6bmWaV23ZJJ/JEVw/ZaQ=
 cloud.google.com/go/trace v1.16.0 h1:GmQovzFc5F0CNfl0VLgL64aoTtu7xsM0YajW2GlG9+E=
 cloud.google.com/go/trace v1.16.0/go.mod h1:r+bdAn16dKLSV1G2D5v3e58IlQlizfxWrUfjx7kM7X0=
+dario.cat/mergo v1.0.2 h1:85+piFYR1tMbRrLcDwR18y4UKJ3aH1Tbzi24VRW1TK8=
+dario.cat/mergo v1.0.2/go.mod h1:E/hbnu0NxMFBjpMIE34DRGLWqDy0g5FuKDhCb31ngxA=
 github.com/GoogleCloudPlatform/opentelemetry-operations-go/detectors/gcp v1.35.0 h1:bN1gA3of5bXtbnLsRPrwfmbbe7A5UWFlcTHseujLnpc=
 github.com/GoogleCloudPlatform/opentelemetry-operations-go/detectors/gcp v1.35.0/go.mod h1:Yj5vHEz/aAepZGliRJsA6uvHAVAQyEwajq9ORCHPxzM=
 github.com/GoogleCloudPlatform/opentelemetry-operations-go/exporter/metric v0.59.0 h1:c/Ivw7FuawPLfrr+zB0LZKeCchO2cAHQpF2qZ6OV7rQ=
@@ -136,6 +138,8 @@ github.com/fatih/color v1.19.0 h1:Zp3PiM21/9Ld6FzSKyL5c/BULoe/ONr9KlbYVOfG8+w=
 github.com/fatih/color v1.19.0/go.mod h1:zNk67I0ZUT1bEGsSGyCZYZNrHuTkJJB+r6Q9VuMi0LE=
 github.com/felixge/httpsnoop v1.1.0 h1:3YtUj32ZZkqZtt3sZZsClsymw/QDuVfpNhoA31zeORc=
 github.com/felixge/httpsnoop v1.1.0/go.mod h1:Zqxgdd+1Rkcz8euOqdr7lqgCRJztwr5hp9vDSi5UZCE=
+github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
+github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
 github.com/fsnotify/fsnotify v1.10.1 h1:b0/UzAf9yR5rhf3RPm9gf3ehBPpf0oZKIjtpKrx59Ho=
 github.com/fsnotify/fsnotify v1.10.1/go.mod h1:TLheqan6HD6GBK6PrDWyDPBaEV8LspOxvPSjC+bVfgo=
 github.com/go-jose/go-jose/v4 v4.1.4 h1:moDMcTHmvE6Groj34emNPLs/qtYXRVcd6S7NHbHz3kA=
@@ -147,8 +151,8 @@ github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/go-quicktest/qt v1.102.0 h1:HSQxCeh5YZH3EL3W39ixjtyaEhcWSXQHtHnMBzSs474=
 github.com/go-quicktest/qt v1.102.0/go.mod h1:p4lGIVX+8Wa6ZPNDvqcxq36XpUDLh42FLetFU7odllI=
-github.com/go-task/slim-sprig/v3 v3.0.0 h1:sUs3vkvUymDpBKi3qH1YSqBQk9+9D/8M2mN1vB6EwHI=
-github.com/go-task/slim-sprig/v3 v3.0.0/go.mod h1:W848ghGpv3Qj3dhTPRyJypKRiqCdHZiAzKg9hl15HA8=
+github.com/go-sprout/sprout v1.0.3 h1:LLuz0D3aYazgbVTOwCVuMor3LOUVYinipXRIdjA/D+I=
+github.com/go-sprout/sprout v1.0.3/go.mod h1:cFFzpnyGGry3cmN0UNCAM1f7AGok6vPVabeYQzBMBZY=
 github.com/go-task/template v0.2.0 h1:xW7ek0o65FUSTbKcSNeg2Vyf/I7wYXFgLUznptvviBE=
 github.com/go-task/template v0.2.0/go.mod h1:dbdoUb6qKnHQi1y6o+IdIrs0J4o/SEhSTA6bbzZmdtc=
 github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
@@ -198,10 +202,14 @@ github.com/mattn/go-isatty v0.0.24 h1:tGZZoVgT/KiqK1c8ocVLeDS8BSWMRd47J3Lbz7vsRe
 github.com/mattn/go-isatty v0.0.24/go.mod h1:nMCL3Zebbrt45jsMDgnfIwz6ydEQApk5oEI3HqDio6A=
 github.com/mattn/go-runewidth v0.0.27 h1:Feg/Oou5zI/wnpgDF6omIU0OokC9GxLC/WRknhVlIR0=
 github.com/mattn/go-runewidth v0.0.27/go.mod h1:3qAiGCV4Koz/yuveO58qUefmUTRm8r0IGEXZ9jeHp/8=
+github.com/mitchellh/copystructure v1.2.0 h1:vpKXTN4ewci03Vljg/q9QvCGUDttBOGBIa15WveJJGw=
+github.com/mitchellh/copystructure v1.2.0/go.mod h1:qLl+cE2AmVv+CoeAwDPye/v+N2HKCj9FbZEVFJRxO9s=
 github.com/mitchellh/go-homedir v1.1.0 h1:lukF9ziXFxDFPkA1vsr5zpc1XuPDn/wFntq5mG+4E0Y=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/hashstructure/v2 v2.0.2 h1:vGKWl0YJqUNxE8d+h8f6NJLcCJrgbhC4NcD46KavDd4=
 github.com/mitchellh/hashstructure/v2 v2.0.2/go.mod h1:MG3aRVU/N29oo/V/IhBX8GR/zz4kQkprJgF2EVszyDE=
+github.com/mitchellh/reflectwalk v1.0.2 h1:G2LzWKi524PWgd3mLHV8Y5k7s6XUvT0Gef6zxSIeXaQ=
+github.com/mitchellh/reflectwalk v1.0.2/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx0jmZXqmk4esnw=
 github.com/muesli/cancelreader v0.2.2 h1:3I4Kt4BQjOR54NavqnDogx/MIoWBFa0StPA8ELUXHmA=
 github.com/muesli/cancelreader v0.2.2/go.mod h1:3XuTXfFS2VjM+HTLZY9Ak0l6eUKfijIfMUZ4EgX0QYo=
 github.com/pierrec/lz4/v4 v4.1.27 h1:+PhzhWDrjRj89TH2sw43nE3+4+W8lSxIuQadEHZyjUk=
@@ -225,6 +233,8 @@ github.com/sebdah/goldie/v2 v2.8.0/go.mod h1:oZ9fp0+se1eapSRjfYbsV/0Hqhbuu3bJVvK
 github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
 github.com/sergi/go-diff v1.4.0 h1:n/SP9D5ad1fORl+llWyN+D6qoUETXNZARKjyY2/KVCw=
 github.com/sergi/go-diff v1.4.0/go.mod h1:A0bzQcvG0E7Rwjx0REVgAGH58e96+X0MeOfepqsbeW4=
+github.com/spf13/cast v1.10.0 h1:h2x0u2shc1QuLHfxi+cTJvs30+ZAHOGRic8uyGTDWxY=
+github.com/spf13/cast v1.10.0/go.mod h1:jNfB8QC9IA6ZuY2ZjDp0KtFO2LZZlg4S/7bzP6qqeHo=
 github.com/spf13/pflag v1.0.10 h1:4EBh2KAYBwaONj6b2Ye1GiHfwjqyROoF4RwYO+vPwFk=
 github.com/spf13/pflag v1.0.10/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/spiffe/go-spiffe/v2 v2.8.1 h1:eXZMLsu+3MLEPJyGJkolqtVrteZfQdUpOWj6LTiDl/E=

internal/templater/funcs.go

@@ -1,150 +1,98 @@
 package templater
 
 import (
+	"log/slog"
 	"maps"
-	"math/rand/v2"
-	"net/url"
-	"os"
-	"path/filepath"
-	"runtime"
-	"strings"
 
-	"github.com/davecgh/go-spew/spew"
-	"github.com/google/uuid"
-	"go.yaml.in/yaml/v3"
-	"mvdan.cc/sh/v3/shell"
-	"mvdan.cc/sh/v3/syntax"
+	"github.com/go-sprout/sprout"
+	"github.com/go-sprout/sprout/registry/backward"
+	"github.com/go-sprout/sprout/registry/checksum"
+	"github.com/go-sprout/sprout/registry/conversion"
+	"github.com/go-sprout/sprout/registry/encoding"
+	"github.com/go-sprout/sprout/registry/env"
+	"github.com/go-sprout/sprout/registry/filesystem"
+	sproutmaps "github.com/go-sprout/sprout/registry/maps"
+	"github.com/go-sprout/sprout/registry/numeric"
+	"github.com/go-sprout/sprout/registry/random"
+	"github.com/go-sprout/sprout/registry/reflect"
+	"github.com/go-sprout/sprout/registry/regexp"
+	"github.com/go-sprout/sprout/registry/slices"
+	"github.com/go-sprout/sprout/registry/std"
+	sproutstrings "github.com/go-sprout/sprout/registry/strings"
+	sprouttime "github.com/go-sprout/sprout/registry/time"
+	"github.com/go-sprout/sprout/registry/uniqueid"
 
-	sprig "github.com/go-task/slim-sprig/v3"
 	"github.com/go-task/template"
+
+	"github.com/go-task/task/v3/internal/templater/taskfuncs"
 )
 
 var templateFuncs template.FuncMap
 
-func init() {
-	taskFuncs := template.FuncMap{
-		"OS":           goos,
-		"ARCH":         goarch,
-		"numCPU":       runtime.NumCPU,
-		"catLines":     catLines,
-		"splitLines":   splitLines,
-		"fromSlash":    filepath.FromSlash,
-		"toSlash":      filepath.ToSlash,
-		"exeExt":       exeExt,
-		"shellQuote":   shellQuote,
-		"splitArgs":    splitArgs,
-		"IsSH":         IsSH, // Deprecated
-		"joinPath":     filepath.Join,
-		"joinEnv":      joinEnv,
-		"joinUrl":      joinUrl,
-		"relPath":      filepath.Rel,
-		"absPath":      filepath.Abs,
-		"merge":        merge,
-		"spew":         spew.Sdump,
-		"fromYaml":     fromYaml,
-		"mustFromYaml": mustFromYaml,
-		"toYaml":       toYaml,
-		"mustToYaml":   mustToYaml,
-		"uuid":         uuid.New,
-		"randIntN":     rand.IntN,
-	}
-
-	// aliases
-	taskFuncs["q"] = taskFuncs["shellQuote"]
-
-	// Deprecated aliases for renamed functions.
-	taskFuncs["FromSlash"] = taskFuncs["fromSlash"]
-	taskFuncs["ToSlash"] = taskFuncs["toSlash"]
-	taskFuncs["ExeExt"] = taskFuncs["exeExt"]
-
-	templateFuncs = template.FuncMap(sprig.TxtFuncMap())
-	maps.Copy(templateFuncs, taskFuncs)
-}
-
-func goos() string {
-	return runtime.GOOS
-}
-
-func goarch() string {
-	return runtime.GOARCH
-}
-
-func catLines(s string) string {
-	s = strings.ReplaceAll(s, "\r\n", " ")
-	return strings.ReplaceAll(s, "\n", " ")
-}
-
-func splitLines(s string) []string {
-	s = strings.ReplaceAll(s, "\r\n", "\n")
-	return strings.Split(s, "\n")
-}
-
-func exeExt() string {
-	if runtime.GOOS == "windows" {
-		return ".exe"
-	}
-	return ""
-}
-
-func shellQuote(str string) (string, error) {
-	return syntax.Quote(str, syntax.LangBash)
+// legacySprigAliases maps the function names Task exposed through slim-sprig
+// onto their sprout equivalents. Only names slim-sprig actually shipped are
+// listed — sprout carries a wider legacy set, but Task never exposed those and
+// should not start now.
+var legacySprigAliases = sprout.FunctionAliasMap{
+	"dateModify":   {"date_modify", "must_date_modify"},
+	"dateInZone":   {"date_in_zone"},
+	"dateAgo":      {"ago"},
+	"trimAll":      {"trimall"},
+	"append":       {"push", "mustPush"},
+	"list":         {"tuple"},
+	"max":          {"biggest"},
+	"toUpper":      {"upper"},
+	"toLower":      {"lower"},
+	"toTitleCase":  {"title"},
+	"base64Encode": {"b64enc"},
+	"base64Decode": {"b64dec"},
+	"base32Encode": {"b32enc"},
+	"base32Decode": {"b32dec"},
+	"pathBase":     {"base"},
+	"pathDir":      {"dir"},
+	"pathExt":      {"ext"},
+	"pathClean":    {"clean"},
+	"pathIsAbs":    {"isAbs"},
+	"expandEnv":    {"expandenv"},
+	"strSlice":     {"toStrings"},
+	"toInt":        {"int", "atoi"},
+	"toInt64":      {"int64"},
+	"toFloat64":    {"float64"},
+	"toOctal":      {"toDecimal"},
 }
 
-func splitArgs(s string) ([]string, error) {
-	return shell.Fields(s, nil)
-}
-
-// Deprecated: now always returns true
-func IsSH() bool {
-	return true
-}
-
-func joinEnv(elem ...string) string {
-	return strings.Join(elem, string(os.PathListSeparator))
-}
-
-func joinUrl(elem ...string) (string, error) {
-	if len(elem) == 0 {
-		return "", nil
-	}
-	// Use net/url.JoinPath rather than path.Join: the latter runs path.Clean,
-	// which collapses the "//" in a URL scheme (e.g. "http://" -> "http:/").
-	return url.JoinPath(elem[0], elem[1:]...)
-}
-
-func merge(base map[string]any, v ...map[string]any) map[string]any {
-	cap := len(v)
-	for _, m := range v {
-		cap += len(m)
-	}
-	result := make(map[string]any, cap)
-	maps.Copy(result, base)
-	for _, m := range v {
-		maps.Copy(result, m)
+func init() {
+	handler := sprout.New(
+		sprout.WithLogger(slog.New(noticeHandler{})),
+		sprout.WithRegistries(
+			taskfuncs.NewRegistry(),
+			backward.NewRegistry(),
+			checksum.NewRegistry(),
+			conversion.NewRegistry(),
+			encoding.NewRegistry(),
+			env.NewRegistry(),
+			filesystem.NewRegistry(),
+			sproutmaps.NewRegistry(),
+			numeric.NewRegistry(),
+			random.NewRegistry(),
+			reflect.NewRegistry(),
+			regexp.NewRegistry(),
+			slices.NewRegistry(),
+			std.NewRegistry(),
+			sproutstrings.NewRegistry(),
+			sprouttime.NewRegistry(),
+			uniqueid.NewRegistry(),
+		),
+	)
+
+	for original, aliases := range legacySprigAliases {
+		_ = sprout.WithAlias(original, aliases...)(handler)
+		for _, alias := range aliases {
+			_ = sprout.WithNotices(sprout.NewDeprecatedNotice(alias, "please use `"+original+"` instead"))(handler)
+		}
 	}
-	return result
-}
 
-func fromYaml(v string) any {
-	output, _ := mustFromYaml(v)
-	return output
-}
-
-func mustFromYaml(v string) (any, error) {
-	var output any
-	err := yaml.Unmarshal([]byte(v), &output)
-	return output, err
-}
-
-func toYaml(v any) string {
-	output, _ := yaml.Marshal(v)
-	return string(output)
-}
-
-func mustToYaml(v any) (string, error) {
-	output, err := yaml.Marshal(v)
-	if err != nil {
-		return "", err
-	}
-	return string(output), nil
+	templateFuncs = template.FuncMap(handler.Build())
+	maps.Copy(templateFuncs, taskfuncs.Overrides())
+	maps.Copy(templateFuncs, sprigSignatureShims(handler))
 }

internal/templater/notices.go

@@ -0,0 +1,57 @@
+package templater
+
+import (
+	"context"
+	"log/slog"
+	"sync"
+	"sync/atomic"
+)
+
+// NoticeFunc receives the deprecation notices that sprout emits when a
+// template calls a deprecated function name or uses a deprecated argument
+// order.
+type NoticeFunc func(format string, args ...any)
+
+// noticeSink is set once the Executor has built its logger. Until then — and
+// the function map is built in an init(), long before that — notices are
+// dropped rather than written to sprout's default stdout handler, which would
+// corrupt the JSON and group output styles.
+var noticeSink atomic.Pointer[NoticeFunc]
+
+// SetNoticeSink installs the destination for template deprecation notices.
+// Passing nil silences them again.
+func SetNoticeSink(fn NoticeFunc) {
+	noticeSeen.Clear()
+	if fn == nil {
+		noticeSink.Store(nil)
+		return
+	}
+	noticeSink.Store(&fn)
+}
+
+type noticeHandler struct{}
+
+func (noticeHandler) Enabled(_ context.Context, level slog.Level) bool {
+	return level >= slog.LevelWarn && noticeSink.Load() != nil
+}
+
+// noticeSeen keeps each distinct notice to a single line. Task renders the
+// same templates several times per run — once per compilation pass — so
+// without this a lone deprecated call would be reported over and over.
+var noticeSeen sync.Map
+
+func (noticeHandler) Handle(_ context.Context, record slog.Record) error {
+	fn := noticeSink.Load()
+	if fn == nil {
+		return nil
+	}
+	if _, dup := noticeSeen.LoadOrStore(record.Message, struct{}{}); dup {
+		return nil
+	}
+	(*fn)("task: %s\n", record.Message)
+	return nil
+}
+
+func (h noticeHandler) WithAttrs([]slog.Attr) slog.Handler { return h }
+
+func (h noticeHandler) WithGroup(string) slog.Handler { return h }