feat: extract code from errgoengine.go, add more tests

Author: nedpals

context.go

@@ -53,3 +53,17 @@ func (data *ContextData) AddVariable(name string, value string) {
 
 	data.Variables[name] = value
 }
+
+func (data *ContextData) AddVariables(vars map[string]string) {
+	if len(vars) == 0 {
+		return
+	}
+
+	if data.Variables == nil {
+		data.Variables = make(map[string]string)
+	}
+
+	for k, v := range vars {
+		data.Variables[k] = v
+	}
+}

errgoengine.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"io/fs"
-	"path/filepath"
 
 	sitter "github.com/smacker/go-tree-sitter"
 )
@@ -58,52 +57,11 @@ func (e *ErrgoEngine) Analyze(workingPath, msg string) (*CompiledErrorTemplate,
 	contextData.Analyzer = template.Language.AnalyzerFactory(contextData)
 	contextData.AddVariable("message", msg)
 
-	groupNames := template.Pattern.SubexpNames()
-	for _, submatches := range template.Pattern.FindAllStringSubmatch(msg, -1) {
-		for idx, matchedContent := range submatches {
-			if len(groupNames[idx]) == 0 {
-				continue
-			}
-
-			contextData.AddVariable(groupNames[idx], matchedContent)
-		}
-	}
+	// extract variables from the error message
+	contextData.AddVariables(template.ExtractVariables(msg))
 
 	// extract stack trace
-	rawStackTraceItem := contextData.Variables["stacktrace"]
-	symbolGroupIdx := template.StackTraceRegex().SubexpIndex("symbol")
-	pathGroupIdx := template.StackTraceRegex().SubexpIndex("path")
-	posGroupIdx := template.StackTraceRegex().SubexpIndex("position")
-	stackTraceMatches := template.StackTraceRegex().FindAllStringSubmatch(rawStackTraceItem, -1)
-
-	for _, submatches := range stackTraceMatches {
-		if len(submatches) == 0 {
-			continue
-		}
-
-		rawSymbolName := ""
-		if symbolGroupIdx != -1 {
-			rawSymbolName = submatches[symbolGroupIdx]
-		}
-		rawPath := submatches[pathGroupIdx]
-		rawPos := submatches[posGroupIdx]
-
-		// convert relative paths to absolute for parsing
-		if len(workingPath) != 0 && !filepath.IsAbs(rawPath) {
-			rawPath = filepath.Clean(filepath.Join(workingPath, rawPath))
-		}
-
-		stLoc := template.Language.LocationConverter(LocationConverterContext{
-			Path:        rawPath,
-			Pos:         rawPos,
-			ContextData: contextData,
-		})
-		if contextData.TraceStack == nil {
-			contextData.TraceStack = TraceStack{}
-		}
-
-		contextData.TraceStack.Add(rawSymbolName, stLoc)
-	}
+	contextData.TraceStack = template.ExtractStackTrace(contextData)
 
 	// open contents of the extracted stack file locations
 	parser := sitter.NewParser()

error_template.go

@@ -2,6 +2,7 @@ package errgoengine
 
 import (
 	"fmt"
+	"path/filepath"
 	"regexp"
 	"strings"
 )
@@ -37,6 +38,61 @@ func (tmp *CompiledErrorTemplate) StackTraceRegex() *regexp.Regexp {
 	return tmp.Language.stackTraceRegex
 }
 
+func (tmp *CompiledErrorTemplate) ExtractVariables(msg string) map[string]string {
+	variables := map[string]string{}
+	groupNames := tmp.Pattern.SubexpNames()
+	for _, submatches := range tmp.Pattern.FindAllStringSubmatch(msg, -1) {
+		for idx, matchedContent := range submatches {
+			if len(groupNames[idx]) == 0 {
+				continue
+			}
+
+			variables[groupNames[idx]] = matchedContent
+		}
+	}
+	return variables
+}
+
+func (tmp *CompiledErrorTemplate) ExtractStackTrace(cd *ContextData) TraceStack {
+	traceStack := TraceStack{}
+	workingPath := cd.WorkingPath
+
+	rawStackTraceItem := cd.Variables["stacktrace"]
+	stackTraceRegex := tmp.StackTraceRegex()
+	symbolGroupIdx := stackTraceRegex.SubexpIndex("symbol")
+	pathGroupIdx := stackTraceRegex.SubexpIndex("path")
+	posGroupIdx := stackTraceRegex.SubexpIndex("position")
+	stackTraceMatches := stackTraceRegex.FindAllStringSubmatch(rawStackTraceItem, -1)
+
+	for _, submatches := range stackTraceMatches {
+		if len(submatches) == 0 {
+			continue
+		}
+
+		rawSymbolName := ""
+		if symbolGroupIdx != -1 {
+			rawSymbolName = submatches[symbolGroupIdx]
+		}
+		rawPath := submatches[pathGroupIdx]
+		rawPos := submatches[posGroupIdx]
+
+		// convert relative paths to absolute for parsing
+		if len(workingPath) != 0 && !filepath.IsAbs(rawPath) {
+			rawPath = filepath.Clean(filepath.Join(workingPath, rawPath))
+		}
+
+		stLoc := tmp.Language.LocationConverter(LocationConverterContext{
+			Path:        rawPath,
+			Pos:         rawPos,
+			ContextData: cd,
+		})
+
+		traceStack.Add(rawSymbolName, stLoc)
+	}
+
+	return traceStack
+}
+
 type ErrorTemplates map[string]*CompiledErrorTemplate
 
 const defaultStackTraceRegex = `(?P<stacktrace>(?:.|\s)*)`