feat: Add simple diagnostics; Improvements

common/errors.go

@@ -0,0 +1,35 @@
+package common
+
+import (
+	"fmt"
+)
+
+type ParserError interface {}
+
+type OptionAlreadyExistsError struct {
+	Option string
+	FoundOnLine uint32
+}
+func (e OptionAlreadyExistsError) Error() string {
+	return fmt.Sprintf("Option %s already exists", e.Option)
+}
+
+type OptionUnknownError struct {
+	Option string
+}
+func (e OptionUnknownError) Error() string {
+	return fmt.Sprintf("Option '%s' does not exist", e.Option)
+}
+
+type MalformedLineError struct {
+	Line string
+}
+func (e MalformedLineError) Error() string {
+	return fmt.Sprintf("Malformed line: %s", e.Line)
+}
+
+type LineNotFoundError struct {}
+func (e LineNotFoundError) Error() string {
+	return "Line not found"
+}
+

common/parser.go

@@ -1,7 +1,6 @@
 package common
 
 import (
-	"fmt"
 	"regexp"
 	"strings"
 )
@@ -34,29 +33,6 @@ type SimpleConfigParser struct {
 	Options SimpleConfigOptions
 }
 
-type OptionAlreadyExistsError struct {
-	Option string
-}
-func (e OptionAlreadyExistsError) Error() string {
-	return fmt.Sprintf("Option %s already exists", e.Option)
-}
-type OptionUnknownError struct {
-	Option string
-}
-func (e OptionUnknownError) Error() string {
-	return fmt.Sprintf("Option '%s' does not exist", e.Option)
-}
-type MalformedLineError struct {
-	Line string
-}
-func (e MalformedLineError) Error() string {
-	return fmt.Sprintf("Malformed line: %s", e.Line)
-}
-type LineNotFoundError struct {}
-func (e LineNotFoundError) Error() string {
-	return "Line not found"
-}
-
 func (p *SimpleConfigParser) AddLine(line string, lineNumber int) error {
 	parts := strings.SplitN(line, p.Options.Separator, 2)
 
@@ -83,6 +59,7 @@ func (p *SimpleConfigParser) AddLine(line string, lineNumber int) error {
 	if _, exists := p.Lines[option]; exists {
 		return OptionAlreadyExistsError{
 			Option: option,
+			FoundOnLine: uint32(lineNumber),
 		}
 	}
 
@@ -118,6 +95,22 @@ func (p *SimpleConfigParser) UpsertOption(option string, value string) {
 	}
 }
 
+func (p *SimpleConfigParser) GetOption(option string) (SimpleConfigLine, error) {
+	if _, exists := p.Lines[option]; exists {
+		return p.Lines[option], nil
+	}
+
+	return SimpleConfigLine{
+			Value: "",
+			Position: SimpleConfigPosition{
+				Line: 0,
+			},
+		}, 
+		OptionUnknownError{
+			Option: option,
+		}
+}
+
 func (p *SimpleConfigParser) ParseFromFile(content string) []error {
 	lines := strings.Split(content, "\n")
 	errors := make([]error, 0)
@@ -142,7 +135,7 @@ func (p *SimpleConfigParser) Clear() {
 }
 
 // TODO: Use better approach: Store an extra array of lines in order; with references to the SimpleConfigLine
-func (p SimpleConfigParser) FindByLineNumber(lineNumber int) (string, SimpleConfigLine, error) {
+func (p *SimpleConfigParser) FindByLineNumber(lineNumber int) (string, SimpleConfigLine, error) {
 	for option, line := range p.Lines {
 		if line.Position.Line == lineNumber {
 			return option, line, nil

handlers/openssh/diagnostics.go

@@ -0,0 +1,56 @@
+package handlers
+
+import (
+	"config-lsp/common"
+	"fmt"
+	"unicode/utf8"
+
+	"github.com/tliron/glsp"
+	protocol "github.com/tliron/glsp/protocol_3_16"
+)
+
+func ClearDiagnostics(context *glsp.Context, uri protocol.DocumentUri) {
+	    context.Notify(
+	"textDocument/publishDiagnostics",
+	protocol.PublishDiagnosticsParams{
+		URI: uri,
+		Diagnostics: []protocol.Diagnostic{},
+	},
+    )
+}
+
+func SendDiagnosticsFromParserErrors(context *glsp.Context, uri protocol.DocumentUri, parserErrors []error) {
+    diagnosticErrors := make([]protocol.Diagnostic, 0)
+
+    for _, parserError := range parserErrors {
+	switch parserError.(type) {
+	case common.OptionAlreadyExistsError: {
+		err := parserError.(common.OptionAlreadyExistsError)
+		existingOption, _ := Parser.GetOption(err.Option)
+
+		diagnosticErrors = append(diagnosticErrors, protocol.Diagnostic{
+		    Range: protocol.Range{
+			Start: protocol.Position{
+			    Line: err.FoundOnLine,
+			    Character: 0,
+			},
+			End: protocol.Position{
+			    Line: err.FoundOnLine,
+			    Character: uint32(utf8.RuneCountInString(err.Option)),
+		        },
+		    },
+		    Message: fmt.Sprintf("Option '%s' has already been declared on line %v", err.Option, existingOption.Position.Line + 1),
+		})
+	}
+	}
+    }
+
+    context.Notify(
+	"textDocument/publishDiagnostics",
+	protocol.PublishDiagnosticsParams{
+		URI: uri,
+		Diagnostics: diagnosticErrors,
+	},
+    )
+}
+

handlers/openssh/text-document-did-change.go

@@ -10,7 +10,14 @@ func TextDocumentDidChange(context *glsp.Context, params *protocol.DidChangeText
 	content := params.ContentChanges[0].(protocol.TextDocumentContentChangeEventWhole).Text
 
 	Parser.Clear()
-		Parser.ParseFromFile(content)
+	errors := Parser.ParseFromFile(content)
+
+	if len(errors) > 0 {
+		SendDiagnosticsFromParserErrors(context, params.TextDocument.URI, errors)
+	} else {
+		ClearDiagnostics(context, params.TextDocument.URI)
+	}
+
 
 	return nil
 }

handlers/openssh/text-document-did-open.go

@@ -17,7 +17,7 @@ func TextDocumentDidOpen(context *glsp.Context, params *protocol.DidOpenTextDocu
 	errors := Parser.ParseFromFile(string(readBytes))
 
 	if len(errors) > 0 {
-		return errors[0]
+		SendDiagnosticsFromParserErrors(context, params.TextDocument.URI, errors)
 	}
 
 	return nil