feat(compiler): support for safe expressions (#27)

Support for `@(some.expression)` and `@!(some.expression)`(escaped)
expressions.

- Added test coverage for parsing expressions
- Added support for safe expressions
- Added test coverage for parsing safe expressions
- Updated lsp to highlight safe expressions correctly

Author: gamebox

gwirl-lsp/template_utils.go

@@ -251,13 +251,20 @@ func absTokensForContent(tt []parser.TemplateTree2) []absToken {
 		case parser.TT2GoExp:
 			length := len(t.Text)
 			var atToken absToken
-			if t.Metadata.Has(parser.TTMDEscape) {
+            if t.Metadata.Has(parser.TTMDSafe) && !t.Metadata.Has(parser.TTMDEscape) {
+                atToken = NewAbsToken(startLine, startCol-2, 2, lsp.SemanticTokenOperator)
+            } else if t.Metadata.Has(parser.TTMDEscape) && t.Metadata.Has(parser.TTMDSafe) {
+                atToken = NewAbsToken(startLine, startCol-3, 3, lsp.SemanticTokenOperator)
+            } else if t.Metadata.Has(parser.TTMDEscape) {
 				atToken = NewAbsToken(startLine, startCol-2, 2, lsp.SemanticTokenOperator)
 			} else {
 				atToken = NewAbsToken(startLine, startCol-1, 1, lsp.SemanticTokenOperator)
 			}
 			token := NewAbsToken(startLine, startCol, length, lsp.SemanticTokenParameter)
 			tokens = append(tokens, atToken, token)
+            if t.Metadata.Has(parser.TTMDSafe) {
+                tokens = append(tokens, NewAbsToken(startLine, startCol + uint32(length), 1, lsp.SemanticTokenOperator))
+            }
 			if t.Children == nil {
 				continue
 			}

internal/parser/nodesv2.go

@@ -99,6 +99,7 @@ type MetadataFlag int
 
 const (
 	TTMDEscape MetadataFlag = 1 << iota
+    TTMDSafe = 2
 )
 
 func (f MetadataFlag) Has(flag MetadataFlag) bool { return f&flag != 0 }
@@ -188,6 +189,20 @@ func NewTT2GoExp(content string, escape bool, transclusions [][]TemplateTree2) T
 	}
 }
 
+func NewTT2GoExpSafe(content string, escape bool) TemplateTree2 {
+    var metadata MetadataFlag
+    metadata.Set(TTMDSafe)
+    if escape {
+        metadata.Set(TTMDEscape)
+    }
+    return TemplateTree2{
+        Type: TT2GoExp,
+        Text: content,
+        Metadata: metadata,
+        Children: [][]TemplateTree2{},
+    }
+}
+
 func NewTT2BlockComment(content string) TemplateTree2 {
 	return TemplateTree2{
 		Type: TT2BlockComment,

internal/parser/parse_expressions_test.go

@@ -0,0 +1,68 @@
+package parser_test
+
+import (
+	"testing"
+
+	"github.com/gamebox/gwirl/internal/parser"
+)
+
+var expressionTests = []ParsingTest{
+    {"simple expression", "@foobar\"", parser.NewTT2GoExp("foobar", false, noChildren)},
+    {"simple method", "@foobar()\"", parser.NewTT2GoExp("foobar()", false, noChildren)},
+    {"complex expression", "@foo.bar\"", parser.NewTT2GoExp("foo.bar", false, noChildren)},
+    {"complex method", "@foo.bar()\"", parser.NewTT2GoExp("foo.bar()", false, noChildren)},
+    {"complex method with params", "@foo.bar(param1, param2)\"", parser.NewTT2GoExp("foo.bar(param1, param2)", false, noChildren)},
+    {"complex method with literal params", "@foo.bar(\"hello\", 123)\"", parser.NewTT2GoExp("foo.bar(\"hello\", 123)", false, noChildren)},
+    {"complex method with struct literal param", "@foo.bar(MyStruct{something, else}, 123)\"", parser.NewTT2GoExp("foo.bar(MyStruct{something, else}, 123)", false, noChildren)},
+    {"complex method with chaining", "@foo.bar().something.else\"", parser.NewTT2GoExp("foo.bar().something.else", false, noChildren)},
+    {"complex method with params with chaining", "@foo.bar(param1, param2).something.else\"", parser.NewTT2GoExp("foo.bar(param1, param2).something.else", false, noChildren)},
+    {"complex method with literal params with chaining", "@foo.bar(\"hello\", 123).something.else\"", parser.NewTT2GoExp("foo.bar(\"hello\", 123).something.else", false, noChildren)},
+   
+    // Transclusion tests
+    {
+        "simple method with transclusion",
+        "@foobar() {\n\t<div>Hello</div>\n}",
+        parser.NewTT2GoExp(
+            "foobar()",
+            false,
+            simpleTransclusionChildren,
+        ),
+    },
+
+    {
+        "complex method with transclusion",
+        "@foo.bar() {\n\t<div>Hello</div>\n}",
+        parser.NewTT2GoExp(
+            "foo.bar()",
+            false,
+            simpleTransclusionChildren,
+        ),
+    },
+
+    {
+        "complex method with param with transclusion",
+        "@foo.bar(param1, param2) {\n\t<div>Hello</div>\n}",
+        parser.NewTT2GoExp(
+            "foo.bar(param1, param2)",
+            false,
+            simpleTransclusionChildren,
+        ),
+    },
+
+    {
+        "complex method with literal params with transclusion",
+        "@foo.bar(\"hello\", 123) {\n\t<div>Hello</div>\n}",
+        parser.NewTT2GoExp(
+            "foo.bar(\"hello\", 123)",
+            false,
+            simpleTransclusionChildren,
+        ),
+    },
+}
+
+func TestExpressionParsing(t *testing.T) {
+    runParserTest(expressionTests, t, func (p *parser.Parser2) *parser.TemplateTree2 {
+        return p.Expression()
+    },"")
+}
+

internal/parser/parse_safe_expression_test.go

@@ -0,0 +1,26 @@
+package parser_test
+
+import (
+    "testing"
+
+    "github.com/gamebox/gwirl/internal/parser"
+)
+
+var safeExpressionTests = []ParsingTest{
+    {"simple expression", "@(foobar)a", parser.NewTT2GoExpSafe("foobar", false)},
+    {"complex expression", "@(foo.bar)a", parser.NewTT2GoExpSafe("foo.bar", false)},
+    {"complex method with chaining", "@(foo.bar().something.else)a", parser.NewTT2GoExpSafe("foo.bar().something.else", false)},
+    {"complex method with params with chaining", "@(foo.bar(param1, param2).something.else)a", parser.NewTT2GoExpSafe("foo.bar(param1, param2).something.else", false)},
+    {"complex method with literal params with chaining", "@(foo.bar(\"hello\", 123).something.else)a", parser.NewTT2GoExpSafe("foo.bar(\"hello\", 123).something.else", false)},
+    {"escaped simple expression", "@!(foobar)a", parser.NewTT2GoExpSafe("foobar", true)},
+    {"escaped complex expression", "@!(foo.bar)a", parser.NewTT2GoExpSafe("foo.bar", true)},
+    {"escaped complex method with chaining", "@!(foo.bar().something.else)a", parser.NewTT2GoExpSafe("foo.bar().something.else", true)},
+    {"escaped complex method with params with chaining", "@!(foo.bar(param1, param2).something.else)a", parser.NewTT2GoExpSafe("foo.bar(param1, param2).something.else", true)},
+    {"escaped complex method with literal params with chaining", "@!(foo.bar(\"hello\", 123).something.else)a", parser.NewTT2GoExpSafe("foo.bar(\"hello\", 123).something.else", true)},
+}
+
+func TestParseSafeExpression(t *testing.T) {
+    runParserTest(safeExpressionTests, t, func(p *parser.Parser2) *parser.TemplateTree2 {
+        return p.SafeExpression()
+    }, "")
+}

internal/parser/parserv2.go

@@ -374,7 +374,28 @@ func expressionContainsKeyword(expressionCode string) (string, bool) {
 	return "", false
 }
 
-func (p *Parser2) expression() *TemplateTree2 {
+func (p *Parser2) SafeExpression() *TemplateTree2 {
+    p.log("SafeExpression")
+    escape := p.checkStr("@!(")
+    if !escape && !p.checkStr("@(") {
+        return nil
+    }
+    var t *TemplateTree2 = nil
+    p.input.regress(1)
+    pos := p.input.offset() + 1
+    code := p.parentheses(true)
+    if code == nil {
+        return t
+    }
+    content := strings.TrimPrefix(strings.TrimSuffix(*code, ")"), "(")
+    exp := NewTT2GoExpSafe(content, escape)
+    t = &exp
+    p.position(t, pos)
+
+    return t
+}
+
+func (p *Parser2) Expression() *TemplateTree2 {
 	p.log("expression")
 	if !p.checkStr("@") {
 		return nil
@@ -622,8 +643,14 @@ func (p *Parser2) Mixed() *TemplateTree2 {
 		p.logf("mixedOpt1: got plain: %v", plain)
 		return plain
 	}
+    p.logf("mixedOpt1: trying SafeExpression")
+    safeExp := p.SafeExpression()
+    if safeExp != nil {
+        p.logf("SafeExpression was not null: %v\n", safeExp)
+        return safeExp
+    }
 	p.logf("mixedOpt1: trying expression")
-	exp := p.expression()
+	exp := p.Expression()
 	if exp != nil {
 		p.logf("expression was not null: %v\n", exp)
 		return exp

internal/parser/testdata/testAll.html.gwirl

@@ -15,5 +15,6 @@
         <h2>B.O.B.</h2>
     } @else {
         <h2>@name</h2>
+        <p>This is a example of a need for a @(name)Safe expression</p>
     }
 </div>

internal/parser/testing_fixtures_test.go

@@ -0,0 +1,79 @@
+package parser_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/gamebox/gwirl/internal/parser"
+)
+
+type ParsingTest struct {
+    name string
+    input string
+    expected parser.TemplateTree2
+}
+var noChildren = [][]parser.TemplateTree2{}
+var simpleTransclusionChildren = [][]parser.TemplateTree2{
+    {
+        parser.NewTT2Plain("\n\t<div>Hello</div>\n"),
+    },
+}
+
+func compareTrees(a parser.TemplateTree2, b parser.TemplateTree2, t *testing.T) {
+    if a.Text != b.Text {
+        t.Fatalf("Expected \"%s\" but got \"%s\"", a.Text, b.Text)
+    }
+    if a.Type != b.Type {
+        t.Fatalf("Expected type %d but got %d", a.Type, b.Type)
+    }
+    if a.Metadata != b.Metadata {
+        t.Fatalf("Expected metadata %d but got %d", a.Metadata, b.Metadata)
+    }
+    if a.Children == nil && b.Children != nil {
+        t.Fatal("Expected the children to be nil")
+    }
+    if a.Children != nil && b.Children == nil {
+        t.Fatal("Expected the children to not be nil")
+    }
+    if len(a.Children) != len(b.Children) {
+        t.Fatalf("Expected %d children, got %d children", len(a.Children), len(b.Children)) 
+    }
+    for i := range a.Children {
+        aChildTree, bChildtree := a.Children[i], b.Children[i]
+        if aChildTree == nil && bChildtree != nil {
+            t.Fatal("Expected the children to be nil")
+        }
+        if aChildTree != nil && bChildtree == nil {
+            t.Fatal("Expected the children to not be nil")
+        }
+        if len(aChildTree) != len(bChildtree) {
+            t.Fatalf("Expected child to have %d trees, got %d trees", len(a.Children), len(b.Children)) 
+        }
+        for childIdx := range aChildTree {
+            compareTrees(aChildTree[childIdx], bChildtree[childIdx], t)
+        }
+    }
+}
+
+func runParserTest(tests []ParsingTest, t *testing.T, parseFn func(*parser.Parser2) *parser.TemplateTree2, debug string) {
+    for i := range tests {
+        test := tests[i]
+        if debug != "" && debug != test.name {
+            continue
+        }
+        success := t.Run(test.name, func(t *testing.T) {
+            p := parser.NewParser2(test.input)
+            if debug != "" {
+                p.SetLogger(os.Stdout)
+            }
+            res := parseFn(&p)
+            if res == nil {
+                t.Fatal("Expected a result, got nil")
+            }
+            compareTrees(test.expected, *res, t)
+        })
+        if !success {
+            t.FailNow()
+        }
+    }
+}