Add RenderContext.ParseTagArgs

chunks/chunk.go

@@ -11,7 +11,7 @@ type Chunk struct {
 	Type       ChunkType
 	SourceInfo SourceInfo
 	Name       string // Name is the tag name of a tag Chunk. E.g. the tag name of "{% if 1 %}" is "if".
-	Parameters string // Parameters is the tag arguments of a tag Chunk. E.g. the tag arguments of "{% if 1 %}" is "1".
+	Args       string // Parameters is the tag arguments of a tag Chunk. E.g. the tag arguments of "{% if 1 %}" is "1".
 	Source     string // Source is the entirety of the chunk, including the "{{", "{%", etc. markers.
 }
 
@@ -38,9 +38,9 @@ func (c Chunk) String() string {
 	case TextChunkType:
 		return fmt.Sprintf("%s{%#v}", c.Type, c.Source)
 	case TagChunkType:
-		return fmt.Sprintf("%s{Tag:%#v, Args:%#v}", c.Type, c.Name, c.Parameters)
+		return fmt.Sprintf("%s{Tag:%#v, Args:%#v}", c.Type, c.Name, c.Args)
 	case ObjChunkType:
-		return fmt.Sprintf("%s{%#v}", c.Type, c.Parameters)
+		return fmt.Sprintf("%s{%#v}", c.Type, c.Args)
 	default:
 		return fmt.Sprintf("%s{%#v}", c.Type, c.Source)
 	}

chunks/marshal.go

@@ -21,7 +21,7 @@ func (c Chunk) MarshalYAML() (interface{}, error) {
 	case TextChunkType:
 		return map[string]interface{}{"text": c.Source}, nil
 	case TagChunkType:
-		return map[string]interface{}{"tag": c.Name, "args": c.Parameters}, nil
+		return map[string]interface{}{"tag": c.Name, "args": c.Args}, nil
 	case ObjChunkType:
 		return map[string]interface{}{"obj": c.Name}, nil
 	default:
@@ -33,7 +33,7 @@ func (c Chunk) MarshalYAML() (interface{}, error) {
 func (n ASTControlTag) MarshalYAML() (interface{}, error) {
 	return map[string]map[string]interface{}{
 		n.cd.name: {
-			"args":     n.Parameters,
+			"args":     n.Args,
 			"body":     n.Body,
 			"branches": n.Branches,
 		}}, nil

chunks/parser.go

@@ -45,7 +45,7 @@ func (s Settings) parseChunks(chunks []Chunk) (ASTNode, error) {
 				rawTag.slices = append(rawTag.slices, c.Source)
 			}
 		case c.Type == ObjChunkType:
-			expr, err := expressions.Parse(c.Parameters)
+			expr, err := expressions.Parse(c.Args)
 			if err != nil {
 				return nil, err
 			}
@@ -82,7 +82,7 @@ func (s Settings) parseChunks(chunks []Chunk) (ASTNode, error) {
 					ccd, ccn, ap = f.cd, f.cn, f.ap
 				}
 			} else if td, ok := s.FindTagDefinition(c.Name); ok {
-				f, err := td(c.Parameters)
+				f, err := td(c.Args)
 				if err != nil {
 					return nil, err
 				}

chunks/render_context.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"strings"
 
 	"github.com/osteele/liquid/expressions"
 )
@@ -16,10 +17,10 @@ type RenderContext interface {
 	Evaluate(expr expressions.Expression) (interface{}, error)
 	EvaluateString(source string) (interface{}, error)
 	EvaluateStatement(tag, source string) (interface{}, error)
+	InnerString() (string, error)
+	ParseTagArgs() (string, error)
 	RenderChild(io.Writer, *ASTControlTag) error
 	RenderChildren(io.Writer) error
-	// RenderTemplate(io.Writer, filename string) (string, error)
-	InnerString() (string, error)
 }
 
 type renderContext struct {
@@ -82,10 +83,6 @@ func (c renderContext) RenderChildren(w io.Writer) error {
 	return c.ctx.RenderASTSequence(w, c.cn.Body)
 }
 
-// func (c renderContext) RenderTemplate(w io.Writer, filename string) (string, error) {
-// 	// TODO use the tags and filters from the current context
-// }
-
 // InnerString renders the children to a string.
 func (c renderContext) InnerString() (string, error) {
 	buf := new(bytes.Buffer)
@@ -94,3 +91,26 @@ func (c renderContext) InnerString() (string, error) {
 	}
 	return buf.String(), nil
 }
+
+func (c renderContext) ParseTagArgs() (string, error) {
+	var args string
+	switch {
+	case c.node != nil:
+		args = c.node.Chunk.Args
+	case c.cn != nil:
+		args = c.cn.Chunk.Args
+	}
+	if strings.Contains(args, "{{") {
+		p, err := c.ctx.settings.Parse(args)
+		if err != nil {
+			return "", err
+		}
+		buf := new(bytes.Buffer)
+		err = p.Render(buf, c.ctx)
+		if err != nil {
+			return "", err
+		}
+		return buf.String(), nil
+	}
+	return args, nil
+}

chunks/scanner.go

@@ -31,7 +31,7 @@ func Scan(data string, pathname string) []Chunk {
 				Type:       ObjChunkType,
 				SourceInfo: si,
 				Source:     source,
-				Parameters: data[m[2]:m[3]],
+				Args:       data[m[2]:m[3]],
 			})
 		case '%':
 			c := Chunk{
@@ -41,7 +41,7 @@ func Scan(data string, pathname string) []Chunk {
 				Name:       data[m[4]:m[5]],
 			}
 			if m[6] > 0 {
-				c.Parameters = data[m[6]:m[7]]
+				c.Args = data[m[6]:m[7]]
 			}
 			out = append(out, c)
 		}

chunks/scanner_test.go

@@ -33,27 +33,27 @@ func TestScanner(t *testing.T) {
 	require.NotNil(t, tokens)
 	require.Len(t, tokens, 1)
 	require.Equal(t, ObjChunkType, tokens[0].Type)
-	require.Equal(t, "obj", tokens[0].Parameters)
+	require.Equal(t, "obj", tokens[0].Args)
 
 	tokens = Scan("{{ obj }}", "")
 	require.NotNil(t, tokens)
 	require.Len(t, tokens, 1)
 	require.Equal(t, ObjChunkType, tokens[0].Type)
-	require.Equal(t, "obj", tokens[0].Parameters)
+	require.Equal(t, "obj", tokens[0].Args)
 
 	tokens = Scan("{%tag args%}", "")
 	require.NotNil(t, tokens)
 	require.Len(t, tokens, 1)
 	require.Equal(t, TagChunkType, tokens[0].Type)
 	require.Equal(t, "tag", tokens[0].Name)
-	require.Equal(t, "args", tokens[0].Parameters)
+	require.Equal(t, "args", tokens[0].Args)
 
 	tokens = Scan("{% tag args %}", "")
 	require.NotNil(t, tokens)
 	require.Len(t, tokens, 1)
 	require.Equal(t, TagChunkType, tokens[0].Type)
 	require.Equal(t, "tag", tokens[0].Name)
-	require.Equal(t, "args", tokens[0].Parameters)
+	require.Equal(t, "args", tokens[0].Args)
 
 	for i, test := range scannerCountTests {
 		t.Run(fmt.Sprintf("%02d", i), func(t *testing.T) {

tags/loop.go

@@ -33,7 +33,7 @@ func parseLoopExpression(source string) (expressions.Expression, error) {
 }
 
 func loopTagParser(node chunks.ASTControlTag) (func(io.Writer, chunks.RenderContext) error, error) {
-	expr, err := parseLoopExpression(node.Parameters)
+	expr, err := parseLoopExpression(node.Args)
 	if err != nil {
 		return nil, err
 	}

tags/tags.go

@@ -28,7 +28,7 @@ func AddStandardTags(settings chunks.Settings) {
 
 func captureTagParser(node chunks.ASTControlTag) (func(io.Writer, chunks.RenderContext) error, error) {
 	// TODO verify syntax
-	varname := node.Parameters
+	varname := node.Args
 	return func(w io.Writer, ctx chunks.RenderContext) error {
 		s, err := ctx.InnerString()
 		if err != nil {
@@ -42,7 +42,7 @@ func captureTagParser(node chunks.ASTControlTag) (func(io.Writer, chunks.RenderC
 func caseTagParser(node chunks.ASTControlTag) (func(io.Writer, chunks.RenderContext) error, error) {
 	// TODO parse error on non-empty node.Body
 	// TODO case can include an else
-	expr, err := expressions.Parse(node.Parameters)
+	expr, err := expressions.Parse(node.Args)
 	if err != nil {
 		return nil, err
 	}
@@ -52,7 +52,7 @@ func caseTagParser(node chunks.ASTControlTag) (func(io.Writer, chunks.RenderCont
 	}
 	cases := []caseRec{}
 	for _, branch := range node.Branches {
-		bfn, err := expressions.Parse(branch.Parameters)
+		bfn, err := expressions.Parse(branch.Args)
 		if err != nil {
 			return nil, err
 		}
@@ -82,7 +82,7 @@ func ifTagParser(polarity bool) func(chunks.ASTControlTag) (func(io.Writer, chun
 			test expressions.Expression
 			body *chunks.ASTControlTag
 		}
-		expr, err := expressions.Parse(node.Parameters)
+		expr, err := expressions.Parse(node.Args)
 		if err != nil {
 			return nil, err
 		}
@@ -98,7 +98,7 @@ func ifTagParser(polarity bool) func(chunks.ASTControlTag) (func(io.Writer, chun
 			case "else":
 			// TODO parse error if this isn't the last branch
 			case "elsif":
-				t, err := expressions.Parse(c.Parameters)
+				t, err := expressions.Parse(c.Args)
 				if err != nil {
 					return nil, err
 				}