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Discovery plugins

MethodAtlas discovers test methods through a plugin system. Each plugin handles one language or test framework. Plugins are loaded automatically at startup via ServiceLoader — placing a plugin JAR on the classpath is enough to activate it.

This page maps the general configuration terms to what they mean in each supported language so you know exactly what to put in your YAML or on the command line.

Configuration model

Every plugin receives three pieces of configuration:

Config knob CLI flag YAML key What it does
File suffixes -file-suffix fileSuffixes Selects which files the plugin should read. Universal — every language has files with extensions. May be prefixed with a plugin ID to target one plugin (see below).
Test markers -test-marker testMarkers Names the identifiers that mark a method as a test. The meaning of "marker" is language-specific (see below). Empty = use plugin defaults.
Properties -property key=value properties Open-ended key/value pairs for plugin-specific settings that do not fit either field above. Plugins ignore keys they do not recognise.

Targeting a suffix at one plugin

By default a -file-suffix (or fileSuffixes: entry) is delivered to every loaded plugin. To restrict a suffix to a single plugin, prefix the value with the plugin's ID and a colon (:):

# "Test.java" → java plugin only; "Test.cs" → dotnet plugin only
./methodatlas \
  -file-suffix java:Test.java \
  -file-suffix dotnet:Test.cs \
  src/

fileSuffixes:
  - java:Test.java
  - dotnet:Test.cs

The colon character is the separator because it cannot appear in a file name on any mainstream operating system (Windows, macOS, Linux). A value without a colon is global and goes to every plugin, which is the correct choice for most single- language projects.

Example value Delivered to
Test.java all plugins
java:Test.java java plugin only
dotnet:BadNaming.cs dotnet plugin only

Built-in plugin IDs: java (methodatlas-discovery-jvm), dotnet (methodatlas-discovery-dotnet), typescript (methodatlas-discovery-typescript), go (methodatlas-discovery-go), python (methodatlas-discovery-python), and powershell (methodatlas-discovery-powershell). Third-party plugins declare their own ID via TestDiscovery.pluginId().

If no matching suffix reaches a plugin (e.g. all entries are targeted at other plugins), that plugin falls back to its language-specific built-in default (Test.java for Java; .cs for .NET).

Java and Kotlin (JVM)

Plugin class: org.egothor.methodatlas.discovery.jvm.JavaTestDiscovery

In Java and Kotlin, a test marker is an annotation simple name.

Default behaviour — automatic framework detection

When testMarkers is empty (the default), the plugin inspects each file's import declarations and picks the right annotation set automatically:

Imports present Annotation set used
org.junit.jupiter.* Test, ParameterizedTest, RepeatedTest, TestFactory, TestTemplate
org.junit.* or junit.framework.* All JUnit 5 annotations plus Theory
org.testng.* Test
None of the above JUnit 5 set (fallback)

Detection is per-file and accumulative: a file that imports both JUnit 4 and JUnit 5 (common during migrations) receives the union of both sets.

Overriding the detected annotation set

Supply annotation simple names with -test-marker or testMarkers. The first value replaces the entire default set; subsequent values append to it.

# JUnit 5 only — disables auto-detection
./methodatlas -test-marker Test -test-marker ParameterizedTest src/test/java

# Custom in-house annotation alongside the standard one
./methodatlas -test-marker Test -test-marker ScenarioTest src/test/java

testMarkers:
  - Test
  - ParameterizedTest
  - ScenarioTest

Common marker values by framework

Framework Marker values to use
JUnit 5 (Jupiter) Test, ParameterizedTest, RepeatedTest, TestFactory, TestTemplate
JUnit 4 Test, Theory
TestNG Test
Custom The simple name of your annotation (without @)
Mixed JUnit 4 + 5 Leave testMarkers empty — auto-detection handles this

The properties map (JVM)

The JVM plugin does not use the properties map. Any keys present are silently ignored.

C# / .NET

Plugin class: org.egothor.methodatlas.discovery.dotnet.DotNetTestDiscovery

In C#, a test marker is an attribute simple name (without the surrounding [ ] brackets). Framework detection is automatic from using directives — leave testMarkers empty unless you need to override it.

Framework Detected by Default markers
xUnit using Xunit; Fact, Theory
NUnit using NUnit.Framework; Test, TestCase, TestCaseSource
MSTest using Microsoft.VisualStudio.TestTools.UnitTesting; TestMethod, DataTestMethod

Tag reading

When MethodAtlas scans a .cs file it reads existing category / trait attributes and records their values in the tags column:

Framework Attribute read Argument used
NUnit [Category("value")] first (and only) argument
xUnit [Trait("Tag", "value")] or [Trait("Category", "value")] second argument (first must be "Tag" or "Category", case-insensitive)
MSTest [TestCategory("value")] first (and only) argument

Tag and display-name write-back

The .NET plugin also ships a SourcePatcher (DotNetSourcePatcher) that writes annotation changes back into .cs files:

Framework Tag written as Display name
NUnit [Category("value")] not supported
xUnit [Trait("Tag", "value")] [Fact(DisplayName = "text")]
MSTest [TestCategory("value")] not supported

Configuration example

# Auto-detection — no markers needed
./methodatlas -file-suffix dotnet:Test.cs src/

# Override to xUnit only
./methodatlas -file-suffix dotnet:Test.cs \
  -test-marker Fact -test-marker Theory \
  src/

fileSuffixes:
  - dotnet:Test.cs
testMarkers:
  - Fact
  - Theory

The properties map (.NET)

The .NET plugin does not currently use the properties map. Any keys present are silently ignored.

Parser scope

The C# parser is built on a structural ANTLR4 grammar (CSharpTest.g4) that focuses on namespaces, type declarations, method declarations, and attribute sections. Method bodies are treated as opaque balanced-brace content. This covers the overwhelming majority of real-world test files, but the grammar is not a full implementation of the C# language specification and may not handle every exotic syntax construct.

When the grammar cannot parse a construct it logs a WARNING that includes the file path, line number, character position, and a description of the problem. ANTLR4 error recovery then continues, so as many test methods as possible are still discovered from the remainder of the file.

If you encounter a parse warning on a valid .cs file, please report it and include the relevant code fragment. Grammar improvements are localised and typically quick to deliver.

TypeScript and JavaScript

Plugin class: org.egothor.methodatlas.discovery.typescript.TypeScriptTestDiscovery Module: methodatlas-discovery-typescript Requires: Node.js 18 or later on the PATH

TypeScript testing frameworks (Jest, Vitest, Mocha) do not use annotations or decorators to mark tests. Tests are identified by function call names (test(…), it(…)). The testMarkers field is not applicable here — leave it empty and use properties instead.

Prerequisites

Node.js 18 or later must be installed and accessible as node on the system PATH. If Node.js is absent or below version 18, the plugin disables itself gracefully and logs a warning; all other plugins continue to function normally.

Default file suffixes

The plugin matches files ending in .test.ts, .spec.ts, .test.tsx, .spec.tsx, .test.js, or .spec.js by default. These defaults are plugin-scoped — they are not delivered to the Java or .NET plugins.

Test-method detection

describe, context, and suite calls are recognised as scope containers. The container name is prepended to the test name in the output:

Source Method recorded as
it('should auth') at top level should auth
describe('AuthService', () => { it('should auth', ...) }) AuthService > should auth
Nested describes Outer > Inner > test name

The test.each, it.each, test.skip, test.only variants are also recognised — the base function name is extracted from the member expression.

Configuration properties

Property key Meaning Default values
functionNames Function call names that identify a test test, it
typescript.poolSize Number of Node.js worker processes min(4, CPU count)
typescript.workerTimeoutSec Per-file worker timeout in seconds 30
typescript.maxConsecutiveRestarts Circuit-breaker restart limit 5
typescript.restartWindowSec Circuit-breaker sliding window in seconds 60 
# Auto-detected defaults — works for Jest, Vitest, Mocha out of the box
./methodatlas \
  -file-suffix typescript:.test.ts \
  -file-suffix typescript:.spec.ts \
  src/

# Custom function names (Jasmine uses 'it' only; custom frameworks vary)
./methodatlas \
  -file-suffix typescript:.spec.ts \
  -property functionNames=it \
  -property functionNames=specify \
  src/

fileSuffixes:
  - typescript:.test.ts
  - typescript:.spec.ts
# testMarkers is intentionally absent — not applicable for TypeScript
properties:
  functionNames:
    - test
    - it
  typescript.workerTimeoutSec:
    - "60"   # increase for very large files

Security model

The TypeScript plugin runs a pre-built, integrity-verified Node.js process for each scan. The security guarantees are:

Bundle integrity — the SHA-256 of the scanner bundle is computed at Gradle build time and embedded in the JAR manifest as TS-Scanner-Bundle-SHA256. At startup the plugin re-computes the hash and refuses to run if it does not match. This detects JAR tampering and corruption before any code executes.

No runtime npm — the bundle (ts-scanner.bundle.js) is a single self-contained file produced by esbuild at build time. No package manager runs at runtime; the only Node.js module loaded is the bundle itself.

File-system sandboxing — when Node.js 20 or later is detected, workers are started with --experimental-permission --allow-fs-read=<scan-root> so the worker process can only read files under the directories being scanned.

Audit logging — every worker start and stop is logged at INFO level with the bundle version, SHA-256 prefix, Node.js version, and OS process ID. Every worker kill is logged with the reason. This gives audit teams a full provenance trail for any MethodAtlas run.

Circuit breaker — if a worker restarts more than typescript.maxConsecutiveRestarts times within typescript.restartWindowSec seconds, the plugin is disabled for the remainder of the run and a WARNING is emitted. This prevents runaway restart loops from consuming system resources.

The properties map (TypeScript)

Key Type Default Description
functionNames List<String> test, it Function call names that identify a test method. Repeated -property functionNames=… values accumulate into a list.
typescript.poolSize int min(4, CPUs) Worker-pool size. Increase for projects with very many test files.
typescript.workerTimeoutSec int 30 Per-file response timeout. Increase for large files or slow machines.
typescript.maxConsecutiveRestarts int 5 Circuit-breaker restart limit.
typescript.restartWindowSec int 60 Circuit-breaker sliding window width.

Go

Plugin class: org.egothor.methodatlas.discovery.go.GoTestDiscovery Module: methodatlas-discovery-go

Go test functions are discovered by parsing each _test.go file with a structural ANTLR4 grammar (GoTest.g4) and matching function declarations against the standard go test convention.

Test function detection

A function is treated as a test if its declaration matches:

func TestXxx(t *testing.T)

where Xxx starts with an upper-case letter or underscore. Benchmark functions (BenchmarkXxx), example functions (ExampleXxx), and fuzz targets (FuzzXxx) are intentionally excluded and will not appear in the output.

Default file suffix

_test.go (configurable via -file-suffix go:_test.go).

Tags and display names

Go has no annotation-based tag or display-name system. The tags column is always empty and display_name is always blank. The testMarkers field has no effect on this plugin and should be left empty.

Configuration example

# Default — auto-detects _test.go files
./methodatlas src/

# Explicit suffix targeting (useful in mixed-language monorepos)
./methodatlas -file-suffix go:_test.go src/

fileSuffixes:
  - go:_test.go

The properties map (Go)

The Go plugin does not use the properties map. Any keys present are silently ignored.

Python

Plugin class: org.egothor.methodatlas.discovery.python.PythonTestDiscovery Module: methodatlas-discovery-python Requires: Python 3.8 or later on the PATH

The Python plugin discovers test functions and methods following the pytest naming conventions. Parsing is performed by a pool of long-lived Python worker processes that run the bundled py-scanner.py script using the standard-library ast module. The AST-based approach correctly handles all valid Python syntax — including decorator stacks, type annotations, and async functions — and reports exact begin/end line numbers.

Prerequisites

Python 3.8 or later must be installed and accessible as python3 (or python) on the system PATH. Python 3.8 is the minimum because ast.Node.end_lineno — used to compute per-function line ranges — was added in that release. If Python is absent or below version 3.8, the plugin disables itself gracefully and logs a warning; all other plugins continue to function normally.

File selection

Two file-naming conventions are supported by default:

Convention Example Active when
test_*.py prefix test_auth.py Always — cannot be disabled via CLI
*_test.py suffix security_test.py Default when no -file-suffix python:… is set

If -file-suffix python:<suffix> is supplied, the suffix check uses that value instead of the default _test.py. The test_ prefix check remains active regardless.

Test function and method detection

The plugin recognises:

  • Module-level functions — any def test_*() or async def test_*() function at module scope.
  • Class methods — def test_*() or async def test_*() methods inside a class whose name starts with Test, ends with Test, or ends with Tests (e.g. TestAuth, AuthTest, AuthTests).

The fully-qualified class name (FQCN) is the dot-separated module path for module-level functions, or the module path suffixed with the class name for methods (auth.test_auth.TestAuth).

Tags from @pytest.mark

Decorator lines immediately before a def test_* are inspected. Any @pytest.mark.<name> decorator contributes name to the tags column. All other decorators are ignored.

@pytest.mark.security
@pytest.mark.slow
def test_token_expiry():
    ...

emits tags = security;slow.

testMarkers — not applicable

pytest identifies tests by function name, not by annotations. The testMarkers field has no effect on this plugin and should be left empty.

Configuration example

# Default — auto-detects test_*.py and *_test.py files
./methodatlas src/

# Explicit suffix targeting (useful in mixed-language monorepos)
./methodatlas -file-suffix python:_test.py src/

fileSuffixes:
  - python:_test.py

Configuration properties (Python)

Property key Meaning Default
python.poolSize Number of Python worker processes min(2, CPU count)
python.workerTimeoutSec Per-file worker timeout in seconds 30
python.maxConsecutiveRestarts Circuit-breaker restart limit 5
python.restartWindowSec Circuit-breaker sliding window in seconds 60 
# Default — auto-detects test_*.py and *_test.py
./methodatlas src/

# Explicit suffix and longer timeout for large files
./methodatlas \
  -file-suffix python:_test.py \
  -property python.workerTimeoutSec=60 \
  src/

fileSuffixes:
  - python:_test.py
properties:
  python.workerTimeoutSec:
    - "60"

The properties map (Python)

Key Type Default Description
python.poolSize int min(2, CPUs) Worker-pool size.
python.workerTimeoutSec int 30 Per-file response timeout in seconds.
python.maxConsecutiveRestarts int 5 Circuit-breaker restart limit.
python.restartWindowSec int 60 Circuit-breaker sliding window in seconds.

PowerShell / Pester

Plugin class: org.egothor.methodatlas.discovery.powershell.PowerShellTestDiscovery Module: methodatlas-discovery-powershell

The PowerShell plugin discovers Pester test cases from It "…" { … } blocks in PowerShell test scripts. No PowerShell runtime is required — parsing is performed entirely in Java using a structural ANTLR4 grammar (PowerShellTest.g4) that covers Describe, Context, and It blocks while treating all other PowerShell content as opaque tokens.

File selection

Default suffixes (both are active unless overridden):

Suffix Example
.Tests.ps1 Auth.Tests.ps1
.Test.ps1 Auth.Test.ps1

Override with -file-suffix powershell:<suffix> to use a different convention (e.g. .ps1 alone for projects that do not follow the Pester suffix convention).

Test case detection

Every It "description" { … } block is emitted as one discovered method, regardless of nesting level. It is matched case-insensitively to support style variants.

Describe "…" and Context "…" blocks are not emitted as separate records — they are used only to derive the FQCN (directory + file stem joined with .).

Tags from -Tag

The -Tag parameter on a Pester Describe, Context, or It block is read and its values are collected into the tags column:

Describe "Auth Module" -Tag "security", "auth" {
    It "rejects expired tokens" -Tag "regression" {
        ...
    }
}

Tags are collected at the It line only. Tags on enclosing Describe/Context blocks are not propagated to child It entries — Pester itself handles tag inheritance at runtime.

testMarkers — not applicable

Pester uses the It keyword, not annotations or attributes. The testMarkers field has no effect on this plugin and should be left empty.

Configuration example

# Default — auto-detects *.Tests.ps1 and *.Test.ps1 files
./methodatlas src/

# Explicit suffix targeting
./methodatlas -file-suffix powershell:.Tests.ps1 \
              -file-suffix powershell:.Test.ps1 \
              src/

fileSuffixes:
  - powershell:.Tests.ps1
  - powershell:.Test.ps1

The properties map (PowerShell)

The PowerShell plugin does not use the properties map. Any keys present are silently ignored.

SAP ABAP / ABAP Unit / ecATT

Plugin class: org.egothor.methodatlas.discovery.abap.ABAPTestDiscovery Module: methodatlas-discovery-abap

The ABAP plugin discovers tests from two SAP test conventions in a single pass — no SAP NetWeaver runtime is required. Parsing is performed entirely in Java using two ANTLR4 grammars (ABAPTest.g4 and ECATTScript.g4) loaded by the same plugin.

Conventions detected

Convention File extension What is emitted
ABAP Unit .abap Each method declared FOR TESTING inside a class flagged FOR TESTING
ecATT .ecl Each FUNCTION … DONE block in an exported ecATT script (transaction SECATT)

File selection

Default suffixes (both are active unless overridden):

Suffix Example
.abap zcl_auth_test.abap
.ecl zecatt_login.ecl

Override with -file-suffix abap:<suffix> to restrict or extend the selection (for example, projects that store ABAP Unit classes under a non-default extension produced by an export tool).

ABAP Unit — detection logic

The plugin walks the lexed token stream rather than a full parse tree. This is deliberate: ABAP has an extremely large statement vocabulary and a strict structural grammar is brittle inside method bodies. Token scanning reacts only to a handful of well-defined markers and ignores everything else.

The scanner emits one discovered method when all three of these hold:

  1. A class is opened with CLASS … DEFINITION … FOR TESTING.
  2. A METHODS: declaration inside that class names a method with the FOR TESTING attribute.
  3. The corresponding CLASS … IMPLEMENTATION. block contains a METHOD <name> … ENDMETHOD. body for that name.

The FQCN is the ABAP class name as written in the source (for example ZCL_AUTH_TEST).

ecATT — detection logic

Each FUNCTION <name> … DONE block is emitted as one test case. The function name is used as the method name; begin and end lines span from the FUNCTION keyword to the closing DONE. The FQCN is the script file stem.

testMarkers — not applicable

ABAP Unit uses the FOR TESTING keyword pair (structurally recognised); ecATT uses the FUNCTION keyword. The testMarkers field has no effect on either detector and should be left empty.

The properties map (ABAP)

The ABAP plugin does not currently use the properties map. Keys present are silently ignored, reserved for future SAP-tool-specific options.

Configuration example

# Default — auto-detects .abap and .ecl files
./methodatlas src/

# Restrict to ABAP Unit only (skip ecATT)
./methodatlas -file-suffix abap:.abap src/

fileSuffixes:
  - abap:.abap
  - abap:.ecl

COBOL — MFUnit / COBOL-Check

Plugin class: org.egothor.methodatlas.discovery.cobol.COBOLTestDiscovery Module: methodatlas-discovery-cobol

The COBOL plugin discovers tests from the two prevailing COBOL unit-test conventions in a single pass — no COBOL compiler or mainframe runtime is required. Parsing uses an ANTLR4 grammar (COBOLTest.g4) and a token-stream scanner that is robust to free-format and fixed-format COBOL sources alike.

Conventions detected

Convention File extensions What is emitted
Micro Focus MFUnit .cbl, .cob, .cobol Each PROCEDURE DIVISION paragraph whose name begins with MFU-TC-
COBOL-Check .cut, also mixed in .cbl Each TestCase '<name>' directive (TestSuite directives are recognised but not emitted)

File selection

Default suffixes (all four are active unless overridden):

Suffix Example
.cbl auth-tests.cbl
.cob auth-tests.cob
.cobol auth-tests.cobol
.cut auth.cut (COBOL-Check)

MFUnit — detection logic

When the lexer recognises an MFU-TC-<rest> paragraph header, the plugin records it as a discovered test paragraph. End-line is the line of the next MFU paragraph header (or end-of-file), minus one.

COBOL-Check — detection logic

When the lexer recognises a TestCase keyword followed by a quoted string, the value with quotes stripped is recorded as the test name. End-line spans to the next TestCase / TestSuite header or end-of-file.

FQCN computation

The FQCN is derived from the file path relative to the scan root (dot-separated, extension stripped). When the PROGRAM-ID paragraph can be extracted from the source, it is appended as the outermost qualifier; otherwise the file stem alone is used.

testMarkers — not applicable

Neither convention uses identifier markers in the JUnit/xUnit sense. MFU-TC-* and TestCase are recognised structurally; testMarkers has no effect and should be left empty.

The properties map (COBOL)

The COBOL plugin does not currently use the properties map. Keys present are silently ignored, reserved for future dialect-specific options (for example, fixed-format column thresholds).

Configuration example

# Default — auto-detects .cbl, .cob, .cobol, and .cut
./methodatlas src/

# COBOL-Check only — skip mainframe MFUnit suites
./methodatlas -file-suffix cobol:.cut src/

fileSuffixes:
  - cobol:.cbl
  - cobol:.cob
  - cobol:.cobol
  - cobol:.cut

Quick reference

Language / framework fileSuffixes testMarkers properties
Java — JUnit 5 Test.java (leave empty — auto-detected) —
Java — TestNG Test.java (leave empty — auto-detected) —
Java — custom annotation Test.java e.g. ScenarioTest —
Kotlin — JUnit 5 Test.kt (leave empty — auto-detected) —
C# — xUnit dotnet:Test.cs Fact, Theory —
C# — NUnit dotnet:Test.cs Test, TestCase —
TypeScript — Jest typescript:.test.ts, typescript:.spec.ts (leave empty) functionNames=test, functionNames=it
TypeScript — Vitest typescript:.test.ts, typescript:.spec.ts (leave empty) functionNames=test, functionNames=it
TypeScript — Mocha typescript:.test.ts, typescript:.spec.ts (leave empty) functionNames=it
JavaScript — Jest typescript:.test.js, typescript:.spec.js (leave empty) functionNames=test, functionNames=it
Go — testing package go:_test.go (not applicable) —
Python — pytest functions python:_test.py (leave empty — name-based) —
Python — pytest classes python:_test.py (leave empty — name-based) —
PowerShell — Pester powershell:.Tests.ps1, powershell:.Test.ps1 (not applicable) —
SAP ABAP — ABAP Unit abap:.abap, abap:.ecl (not applicable — FOR TESTING is recognised structurally) —
COBOL — MFUnit / COBOL-Check cobol:.cbl, cobol:.cob, cobol:.cobol, cobol:.cut (not applicable — MFU-TC-* paragraphs and TestCase directives are recognised structurally) —

Source write-back (SourcePatcher) support

A second SPI, org.egothor.methodatlas.api.SourcePatcher, is used by the -apply-tags and -apply-tags-from-csv modes to write annotation decisions back into source files. Not every discovery plugin ships one — and that is by design: the SPI is only implemented where MethodAtlas can do a safe, formatting-preserving edit.

Plugin Discovery SourcePatcher What -apply-tags does
jvm ✓ JavaSourcePatcher Inserts @DisplayName and @Tag via JavaParser, preserving comments and whitespace
dotnet ✓ DotNetSourcePatcher Inserts [Category] / [Trait] / [TestCategory] and xUnit DisplayName=
typescript ✓ (none) File is recognised but skipped with a per-file notice
go ✓ (none) File is recognised but skipped with a per-file notice
python ✓ (none) File is recognised but skipped with a per-file notice
powershell ✓ (none) File is recognised but skipped with a per-file notice
abap ✓ (none) File is recognised but skipped with a per-file notice
cobol ✓ (none) File is recognised but skipped with a per-file notice

The skip notice has the form:

Apply-tags: skipped <path> — source write-back is not supported for this language (currently Java and C# only)

and the completion summary appends an aggregate skip count when at least one file was skipped. Skipped files do not cause a non-zero exit code; treat the constraint as a known scope limit, not an error. The GUI gates the Stage and "Accept All AI Tags" buttons identically: if the currently selected method lives in a file whose language has no SourcePatcher, the buttons are disabled and a tooltip explains that source write-back is not available for that language.

If you need to add SourcePatcher support for an additional language, implement the SPI (see SourcePatcher.java) and register it in META-INF/services/org.egothor.methodatlas.api.SourcePatcher inside your plugin JAR.

See also