feat: support for Java.InvalidMethodDeclarationError

Author: nedpals

error_templates/java/invalid_method_declaration_error.go

@@ -0,0 +1,56 @@
+package java
+
+import (
+	"fmt"
+	"strings"
+
+	lib "github.com/nedpals/errgoengine"
+)
+
+type invalidMethodDeclarationErrorCtx struct {
+	declNode        lib.SyntaxNode
+	returnTypeToAdd lib.Symbol
+}
+
+var InvalidMethodDeclarationError = lib.ErrorTemplate{
+	Name:              "InvalidMethodDeclarationError",
+	Pattern:           comptimeErrorPattern("invalid method declaration; return type required"),
+	StackTracePattern: comptimeStackTracePattern,
+	OnAnalyzeErrorFn: func(cd *lib.ContextData, m *lib.MainError) {
+		iCtx := invalidMethodDeclarationErrorCtx{}
+		pos := m.ErrorNode.StartPos
+
+		lib.QueryNode(m.Document.RootNode(), strings.NewReader("(constructor_declaration) @method"), func(ctx lib.QueryNodeCtx) bool {
+			match := ctx.Cursor.FilterPredicates(ctx.Match, []byte(m.Nearest.Doc.Contents))
+			for _, c := range match.Captures {
+				pointA := c.Node.StartPoint()
+				pointB := c.Node.EndPoint()
+				if uint32(pos.Line) >= pointA.Row+1 && uint32(pos.Line) <= pointB.Row+1 {
+					node := lib.WrapNode(m.Nearest.Doc, c.Node)
+					iCtx.declNode = node
+					m.Nearest = node.ChildByFieldName("name")
+					return false
+				}
+			}
+			return true
+		})
+
+		iCtx.returnTypeToAdd = lib.UnwrapReturnType(cd.FindSymbol(m.Nearest.Text(), m.Nearest.StartPosition().Index))
+		m.Context = iCtx
+	},
+	OnGenExplainFn: func(cd *lib.ContextData, gen *lib.ExplainGenerator) {
+		gen.Add("This error occurs when there is an invalid method declaration, and a return type is missing.")
+	},
+	OnGenBugFixFn: func(cd *lib.ContextData, gen *lib.BugFixGenerator) {
+		ctx := cd.MainError.Context.(invalidMethodDeclarationErrorCtx)
+
+		gen.Add("Add the return type to the method declaration", func(s *lib.BugFixSuggestion) {
+			s.AddStep("Specify the return type of the `%s` method", cd.MainError.Nearest.Text()).
+				AddFix(lib.FixSuggestion{
+					NewText:       fmt.Sprintf("%s ", ctx.returnTypeToAdd.Name()),
+					StartPosition: cd.MainError.Nearest.StartPosition(),
+					EndPosition:   cd.MainError.Nearest.StartPosition(),
+				})
+		})
+	},
+}

error_templates/java/java.go

@@ -35,6 +35,7 @@ func LoadErrorTemplates(errorTemplates *lib.ErrorTemplates) {
 	errorTemplates.MustAdd(java.Language, UnclosedStringLiteralError)
 	errorTemplates.MustAdd(java.Language, CannotBeAppliedError)
 	errorTemplates.MustAdd(java.Language, BracketMismatchError)
+	errorTemplates.MustAdd(java.Language, InvalidMethodDeclarationError)
 }
 
 func runtimeErrorPattern(errorName string, pattern string) string {

error_templates/java/test_files/invalid_method_declaration_error/InvalidMethodExample.java

@@ -0,0 +1,11 @@
+public class InvalidMethodExample {
+    public static void main(String[] args) {
+        int result = addNumbers(5, 10);
+        System.out.println("Sum: " + result);
+    }
+
+    // Invalid method declaration with missing return type
+    addNumbers(int a, int b) {
+        return a + b;
+    }
+}

error_templates/java/test_files/invalid_method_declaration_error/test.txt

@@ -0,0 +1,29 @@
+template: "Java.InvalidMethodDeclarationError"
+---
+InvalidMethodExample.java:8: error: invalid method declaration; return type required
+    addNumbers(int a, int b) {
+    ^
+1 error
+===
+template: "Java.InvalidMethodDeclarationError"
+---
+# InvalidMethodDeclarationError
+This error occurs when there is an invalid method declaration, and a return type is missing.
+```
+    // Invalid method declaration with missing return type
+    addNumbers(int a, int b) {
+    ^^^^^^^^^^
+        return a + b;
+    }
+```
+## Steps to fix
+### Add the return type to the method declaration
+Specify the return type of the `addNumbers` method.
+```diff
+
+    // Invalid method declaration with missing return type
+-     addNumbers(int a, int b) {
++     int addNumbers(int a, int b) {
+        return a + b;
+    }
+```

languages/java/symbols.txt

@@ -18,6 +18,17 @@
         declarator: (variable_declarator
         	name: (identifier) @variable.name
           value: (_)? @variable.content) @variable.declaration) @variable
+
+    (constructor_declaration
+      name: (identifier) @method.name
+      parameters: (formal_parameters
+        (formal_parameter
+          type: (_) @parameter.return-type
+          name: (identifier) @parameter.name)? @parameter) @parameters
+          body: (constructor_body
+            (return_statement 
+              (_) @block.content)?) @block) @method
+
     (method_declaration
         type: (_) @method.return-type
         name: (identifier) @method.name