Replace expressions engine (#133)

Author: ChristopherHX

go.mod

@@ -21,7 +21,6 @@ require (
 	github.com/opencontainers/image-spec v1.1.1
 	github.com/opencontainers/selinux v1.12.0
 	github.com/pkg/errors v0.9.1
-	github.com/rhysd/actionlint v1.7.7
 	github.com/sabhiram/go-gitignore v0.0.0-20210923224102-525f6e181f06
 	github.com/sirupsen/logrus v1.9.3
 	github.com/spf13/cobra v1.10.1
@@ -49,7 +48,6 @@ require (
 require (
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/ProtonMail/go-crypto v1.1.6 // indirect
-	github.com/bmatcuk/doublestar/v4 v4.8.0 // indirect
 	github.com/cloudflare/circl v1.6.1 // indirect
 	github.com/containerd/errdefs/pkg v0.3.0 // indirect
 	github.com/containerd/log v0.1.0 // indirect
@@ -59,7 +57,6 @@ require (
 	github.com/docker/docker-credential-helpers v0.8.2 // indirect
 	github.com/docker/go-units v0.5.0 // indirect
 	github.com/emirpasic/gods v1.18.1 // indirect
-	github.com/fatih/color v1.18.0 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/go-git/gcfg v1.5.1-0.20230307220236-3a3c6141e376 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
@@ -73,8 +70,6 @@ require (
 	github.com/kevinburke/ssh_config v1.2.0 // indirect
 	github.com/klauspost/compress v1.18.0 // indirect
 	github.com/mattn/go-colorable v0.1.14 // indirect
-	github.com/mattn/go-runewidth v0.0.16 // indirect
-	github.com/mattn/go-shellwords v1.0.12 // indirect
 	github.com/mgutz/ansi v0.0.0-20200706080929-d51e80ef957d // indirect
 	github.com/moby/docker-image-spec v1.3.1 // indirect
 	github.com/moby/sys/atomicwriter v0.1.0 // indirect
@@ -86,8 +81,6 @@ require (
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/pjbgf/sha1cd v0.3.2 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/rivo/uniseg v0.4.7 // indirect
-	github.com/robfig/cron/v3 v3.0.1 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/sergi/go-diff v1.3.2-0.20230802210424-5b0b94c5c0d3 // indirect
 	github.com/skeema/knownhosts v1.3.1 // indirect

go.sum

@@ -15,8 +15,6 @@ github.com/Netflix/go-expect v0.0.0-20220104043353-73e0943537d2 h1:+vx7roKuyA63n
 github.com/Netflix/go-expect v0.0.0-20220104043353-73e0943537d2/go.mod h1:HBCaDeC1lPdgDeDbhX8XFpy1jqjK0IBG8W5K+xYqA0w=
 github.com/ProtonMail/go-crypto v1.1.6 h1:ZcV+Ropw6Qn0AX9brlQLAUXfqLBc7Bl+f/DmNxpLfdw=
 github.com/ProtonMail/go-crypto v1.1.6/go.mod h1:rA3QumHc/FZ8pAHreoekgiAbzpNsfQAosU5td4SnOrE=
-github.com/actions-oss/act-cli-actionlint v0.0.0-20250517100532-8f847f29ba36 h1:QnIPcWM4eVfqRUB3B6sLOwEJrMrTa64qrVqzxF5A21U=
-github.com/actions-oss/act-cli-actionlint v0.0.0-20250517100532-8f847f29ba36/go.mod h1:AE6I6vJEkNaIfWqC2GNE5spIJNhxf8NCtLEKU4NnUXg=
 github.com/adrg/xdg v0.5.3 h1:xRnxJXne7+oWDatRhR1JLnvuccuIeCoBu2rtuLqQB78=
 github.com/adrg/xdg v0.5.3/go.mod h1:nlTsY+NNiCBGCK2tpm09vRqfVzrc2fLmXGpBLF0zlTQ=
 github.com/andreaskoch/go-fswatch v1.0.0 h1:la8nP/HiaFCxP2IM6NZNUCoxgLWuyNFgH0RligBbnJU=
@@ -27,8 +25,6 @@ github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5 h1:0CwZNZbxp69SHPd
 github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5/go.mod h1:wHh0iHkYZB8zMSxRWpUBQtwG5a7fFgvEO+odwuTv2gs=
 github.com/avast/retry-go v3.0.0+incompatible h1:4SOWQ7Qs+oroOTQOYnAHqelpCO0biHSxpiH9JdtuBj0=
 github.com/avast/retry-go v3.0.0+incompatible/go.mod h1:XtSnn+n/sHqQIpZ10K1qAevBhOOCWBLXXy3hyiqqBrY=
-github.com/bmatcuk/doublestar/v4 v4.8.0 h1:DSXtrypQddoug1459viM9X9D3dp1Z7993fw36I2kNcQ=
-github.com/bmatcuk/doublestar/v4 v4.8.0/go.mod h1:xBQ8jztBU6kakFMg+8WGxn0c6z1fTSPVIjEY1Wr7jzc=
 github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
 github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
 github.com/cloudflare/circl v1.6.1 h1:zqIqSPIndyBh1bjLVVDHMPpVKqp8Su/V+6MeDzzQBQ0=
@@ -65,8 +61,6 @@ github.com/elazarl/goproxy v1.7.2 h1:Y2o6urb7Eule09PjlhQRGNsqRfPmYI3KKQLFpCAV3+o
 github.com/elazarl/goproxy v1.7.2/go.mod h1:82vkLNir0ALaW14Rc399OTTjyNREgmdL2cVoIbS6XaE=
 github.com/emirpasic/gods v1.18.1 h1:FXtiHYKDGKCW2KzwZKx0iC0PQmdlorYgdFG9jPXJ1Bc=
 github.com/emirpasic/gods v1.18.1/go.mod h1:8tpGGwCnJ5H4r6BWwaV6OrWmMoPhUl5jm/FMNAnJvWQ=
-github.com/fatih/color v1.18.0 h1:S8gINlzdQ840/4pfAwic/ZE0djQEH3wM94VfqLTZcOM=
-github.com/fatih/color v1.18.0/go.mod h1:4FelSpRwEGDpQ12mAdzqdOukCy4u8WUtOY6lkT/6HfU=
 github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
 github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/gliderlabs/ssh v0.3.8 h1:a4YXD1V7xMF9g5nTkdfnja3Sxy1PVDCj1Zg4Wb8vY6c=
@@ -127,10 +121,6 @@ github.com/mattn/go-colorable v0.1.14/go.mod h1:6LmQG8QLFO4G5z1gPvYEzlUgJ2wF+stg
 github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
-github.com/mattn/go-runewidth v0.0.16 h1:E5ScNMtiwvlvB5paMFdw9p4kSQzbXFikJ5SQO6TULQc=
-github.com/mattn/go-runewidth v0.0.16/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
-github.com/mattn/go-shellwords v1.0.12 h1:M2zGm7EW6UQJvDeQxo4T51eKPurbeFbe8WtebGE2xrk=
-github.com/mattn/go-shellwords v1.0.12/go.mod h1:EZzvwXDESEeg03EKmM+RmDnNOPKG4lLtQsUlTZDWQ8Y=
 github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b/go.mod h1:01TrycV0kFyexm33Z7vhZRXopbI8J3TDReVlkTgMUxE=
 github.com/mgutz/ansi v0.0.0-20200706080929-d51e80ef957d h1:5PJl274Y63IEHC+7izoQE9x6ikvDFZS2mDVS3drnohI=
 github.com/mgutz/ansi v0.0.0-20200706080929-d51e80ef957d/go.mod h1:01TrycV0kFyexm33Z7vhZRXopbI8J3TDReVlkTgMUxE=
@@ -166,11 +156,6 @@ github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 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/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
-github.com/rivo/uniseg v0.4.7 h1:WUdvkW8uEhrYfLC4ZzdpI2ztxP1I582+49Oc5Mq64VQ=
-github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
-github.com/robfig/cron/v3 v3.0.1 h1:WdRxkvbJztn8LMz/QEvLN5sBU+xKpSqwwUO1Pjr4qDs=
-github.com/robfig/cron/v3 v3.0.1/go.mod h1:eQICP3HwyT7UooqI/z+Ov+PtYAWygg1TEWWzGIFLtro=
 github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
 github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
 github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=

internal/eval/functions/format.go

@@ -0,0 +1,122 @@
+package functions
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Format evaluates a format string with the supplied arguments.
+// It behaves like the C# implementation in the repository –
+// it supports escaped braces and numeric argument indices.
+// Format specifiers (e.g. :D) are recognised but currently ignored.
+func Format(formatStr string, args ...interface{}) (string, error) {
+	var sb strings.Builder
+	i := 0
+	for i < len(formatStr) {
+		lbrace := strings.IndexByte(formatStr[i:], '{')
+		rbrace := strings.IndexByte(formatStr[i:], '}')
+
+		// left brace
+		if lbrace >= 0 && (rbrace < 0 || rbrace > lbrace) {
+			l := i + lbrace
+
+			sb.WriteString(formatStr[i:l])
+
+			// escaped left brace
+			if l+1 < len(formatStr) && formatStr[l+1] == '{' {
+				sb.WriteString(formatStr[l : l+1])
+				i = l + 2
+				continue
+			}
+
+			// normal placeholder
+			if rbrace > lbrace+1 {
+				// read index
+				idx, endIdx, ok := readArgIndex(formatStr, l+1)
+				if !ok {
+					return "", fmt.Errorf("invalid format string: %s", formatStr)
+				}
+				// read optional format specifier
+				spec, r, ok := readFormatSpecifiers(formatStr, endIdx+1)
+				if !ok {
+					return "", fmt.Errorf("invalid format string: %s", formatStr)
+				}
+				if idx >= len(args) {
+					return "", fmt.Errorf("argument index %d out of range", idx)
+				}
+				// append argument (format specifier is ignored here)
+				arg := args[idx]
+				sb.WriteString(fmt.Sprintf("%v", arg))
+				if spec != "" {
+					// placeholder for future specifier handling
+					_ = spec
+				}
+				i = r + 1
+				continue
+			}
+			return "", fmt.Errorf("invalid format string: %s", formatStr)
+		}
+
+		// right brace
+		if rbrace >= 0 {
+			// escaped right brace
+			if i+rbrace+1 < len(formatStr) && formatStr[i+rbrace+1] == '}' {
+				sb.WriteString(formatStr[i : i+rbrace+1])
+				i += rbrace + 2
+				continue
+			}
+			return "", fmt.Errorf("invalid format string: %s", formatStr)
+		}
+
+		// rest of string
+		sb.WriteString(formatStr[i:])
+		break
+	}
+	return sb.String(), nil
+}
+
+// readArgIndex parses a decimal number starting at pos.
+// It returns the parsed value, the index of the last digit and true on success.
+func readArgIndex(s string, pos int) (int, int, bool) {
+	start := pos
+	for pos < len(s) && s[pos] >= '0' && s[pos] <= '9' {
+		pos++
+	}
+	if start == pos {
+		return 0, 0, false
+	}
+	idx, err := strconv.Atoi(s[start:pos])
+	if err != nil {
+		return 0, 0, false
+	}
+	return idx, pos - 1, true
+}
+
+// readFormatSpecifiers reads an optional format specifier block.
+// It returns the specifier string, the index of the closing '}' and true on success.
+func readFormatSpecifiers(s string, pos int) (string, int, bool) {
+	if pos >= len(s) {
+		return "", 0, false
+	}
+	if s[pos] == '}' {
+		return "", pos, true
+	}
+	if s[pos] != ':' {
+		return "", 0, false
+	}
+	pos++ // skip ':'
+	start := pos
+	for pos < len(s) {
+		if s[pos] == '}' {
+			return s[start:pos], pos, true
+		}
+		if s[pos] == '}' && pos+1 < len(s) && s[pos+1] == '}' {
+			// escaped '}'
+			pos += 2
+			continue
+		}
+		pos++
+	}
+	return "", 0, false
+}

internal/eval/functions/format_test.go

@@ -0,0 +1,14 @@
+package functions
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFormat(t *testing.T) {
+	s, err := Format("Hello {0}, you have {1} new messages", "Alice", 5)
+	assert.NoError(t, err)
+	fmt.Println(s) // Hello Alice, you have 5 new messages
+}