tessl/maven-org-scoverage--scalac-scoverage-plugin

Comprehensive code coverage tool for Scala providing statement and branch coverage through compiler plugin instrumentation and report generation

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Pending

Overview

Eval results

Files

XML Report Generation

Name: tessl/maven-org-scoverage--scalac-scoverage-plugin
Author: tessl

The ScoverageXmlWriter generates structured XML coverage reports in the scoverage format for programmatic consumption, CI/CD integration, and archival purposes. The XML format provides complete coverage data including statement details, method information, and hierarchical package/class organization.

Core API

ScoverageXmlWriter Class

class ScoverageXmlWriter(
  sourceDirectories: Seq[File],
  outputDir: File,
  debug: Boolean,
  sourceEncoding: Option[String]
) extends BaseReportWriter(sourceDirectories, outputDir, sourceEncoding) {
  def write(coverage: Coverage): Unit
}

Constructor Parameters:

sourceDirectories: Sequence of source directories for relative path calculation
outputDir: Directory where XML report will be generated
debug: Whether to include debug information in the XML output
sourceEncoding: Optional character encoding for reading source files

Methods:

write(coverage: Coverage): Unit - Generates XML report file

Alternative Constructor

// Single source directory constructor
class ScoverageXmlWriter(
  sourceDir: File,
  outputDir: File,
  debug: Boolean,
  sourceEncoding: Option[String]
)

Usage Examples

Basic XML Report Generation

import java.io.File
import scoverage.reporter.ScoverageXmlWriter
import scoverage.domain.Coverage

val sourceDirectories = Seq(new File("src/main/scala"))
val outputDir = new File("target/scoverage-report")
val debug = false
val writer = new ScoverageXmlWriter(sourceDirectories, outputDir, debug, Some("UTF-8"))

val coverage: Coverage = loadCoverageData()
writer.write(coverage)

Debug Mode XML Generation

import java.io.File
import scoverage.reporter.ScoverageXmlWriter

// Debug mode includes additional statement details like symbol names and tree names
val writer = new ScoverageXmlWriter(
  sourceDirectories = Seq(new File("src/main/scala")),
  outputDir = new File("target/scoverage-report"),
  debug = true,
  sourceEncoding = Some("UTF-8")
)

val coverage: Coverage = loadCoverageData()
writer.write(coverage)

CI/CD Integration Example

// Generate XML report for automated processing
val xmlWriter = new ScoverageXmlWriter(
  sourceDirectories = projectSourceDirs,
  outputDir = buildOutputDir,
  debug = false, // Minimal output for CI processing
  sourceEncoding = Some("UTF-8")
)

xmlWriter.write(coverage)

// The generated scoverage.xml can then be parsed by CI tools
val reportFile = new File(buildOutputDir, "scoverage.xml")
// Process with CI/coverage tools...

Generated XML Structure

Standard Mode Output

The XML report includes the following hierarchical structure:

<scoverage statement-count="1250" 
           statements-invoked="1100"
           statement-rate="88.00"
           branch-rate="82.50"
           version="1.0"
           timestamp="1609459200000">
  <packages>
    <package name="com.example.myapp" 
             statement-count="500"
             statements-invoked="450"
             statement-rate="90.00">
      <classes>
        <class name="com.example.myapp.MyClass"
               filename="MyClass.scala"
               statement-count="50"
               statements-invoked="45"
               statement-rate="90.00"
               branch-rate="85.00">
          <methods>
            <method name="myMethod"
                    statement-count="10"
                    statements-invoked="9"
                    statement-rate="90.00"
                    branch-rate="80.00">
              <statements>
                <statement package="com.example.myapp"
                          class="MyClass"
                          class-type="Class"
                          full-class-name="com.example.myapp.MyClass"
                          source="MyClass.scala"
                          method="myMethod"
                          start="150"
                          end="175"
                          line="10"
                          branch="false"
                          invocation-count="5"
                          ignored="false"/>
              </statements>
            </method>
          </methods>
        </class>
      </classes>
    </package>
  </packages>
</scoverage>

Debug Mode Output

When debug = true, statements include additional debugging information:

<statement package="com.example.myapp"
          class="MyClass"
          class-type="Class"
          full-class-name="com.example.myapp.MyClass"
          source="MyClass.scala"
          method="myMethod"
          start="150"
          end="175"
          line="10"
          symbol="scala.Predef.println"
          tree="Apply"
          branch="false"
          invocation-count="5"
          ignored="false">
  println("Hello World")
</statement>

Output Files

File Naming

Standard mode: scoverage.xml
Debug mode: scoverage-debug.xml

File Location

Reports are written to the specified outputDir directory.

XML Schema Details

Root Element Attributes

statement-count: Total number of statements in the codebase
statements-invoked: Number of statements that were executed
statement-rate: Statement coverage percentage (formatted to 2 decimal places)
branch-rate: Branch coverage percentage (formatted to 2 decimal places)
version: Scoverage XML format version
timestamp: Report generation timestamp (milliseconds since epoch)

Package Element Attributes

name: Package name (fully qualified)
statement-count: Statements in this package
statements-invoked: Invoked statements in this package
statement-rate: Package-level statement coverage percentage

Class Element Attributes

name: Fully qualified class name
filename: Relative path to source file
statement-count: Statements in this class
statements-invoked: Invoked statements in this class
statement-rate: Class-level statement coverage percentage
branch-rate: Class-level branch coverage percentage

Method Element Attributes

name: Method name with parameter signature
statement-count: Statements in this method
statements-invoked: Invoked statements in this method
statement-rate: Method-level statement coverage percentage
branch-rate: Method-level branch coverage percentage

Statement Element Attributes

package: Package containing the statement
class: Simple class name
class-type: Type of class (Class, Object, or Trait)
full-class-name: Fully qualified class name
source: Relative path to source file
method: Method containing the statement
start: Character offset start position
end: Character offset end position
line: Line number in source file
branch: Whether this statement represents a branch point
invocation-count: Number of times statement was executed
ignored: Whether statement was excluded from coverage

Debug-Only Statement Attributes

symbol: Scala symbol name (e.g., "scala.Predef.println")
tree: Scala compiler tree type (e.g., "Apply", "Select")

Integration with Build Tools

SBT Integration

// Generate XML report after coverage collection
val coverage = loadCoverageData()
val xmlWriter = new ScoverageXmlWriter(
  sourceDirectories = (Compile / scalaSource).value :: Nil,
  outputDir = crossTarget.value,
  debug = false,
  sourceEncoding = Some("UTF-8")
)
xmlWriter.write(coverage)

Gradle Integration

// Using Array constructor for Gradle compatibility
val sourceArray: Array[File] = sourceDirectories.toArray
val xmlWriter = new ScoverageXmlWriter(sourceArray, outputDir, debug, encoding)
xmlWriter.write(coverage)

Error Handling

Common Issues:

IOException: File writing permissions or disk space issues
RuntimeException: Invalid source directory paths or canonical path resolution failures
IllegalArgumentException: Invalid coverage data or missing statement information

Best Practices:

Ensure output directory exists and is writable
Verify all source directories are accessible
Use debug mode only when needed as it increases file size significantly
Consider XML file size for large codebases (debug mode can be very large)

Install with Tessl CLI

npx tessl i tessl/maven-org-scoverage--scalac-scoverage-plugin

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