Port coverage filter options for packages and files (#19727)

- Add `-coverage-exclude-packages` option that excludes packages and
classes
  from generating coverage
- Add `-coverage-exclude-files` option that excludes files from
  generating coverage

.gitignore

@@ -99,7 +99,3 @@ docs/_spec/.jekyll-metadata
 
 # scaladoc related
 scaladoc/output/
-
-#coverage
-coverage/
-

compiler/src/dotty/tools/dotc/config/ScalaSettings.scala

@@ -127,6 +127,8 @@ trait CommonScalaSettings:
 
   /* Coverage settings */
   val coverageOutputDir = PathSetting("-coverage-out", "Destination for coverage classfiles and instrumentation data.", "", aliases = List("--coverage-out"))
+  val coverageExcludeClasslikes: Setting[List[String]] = MultiStringSetting("-coverage-exclude-classlikes", "packages, classes and modules", "List of regexes for packages, classes and modules to exclude from coverage.", aliases = List("--coverage-exclude-classlikes"))
+  val coverageExcludeFiles: Setting[List[String]] = MultiStringSetting("-coverage-exclude-files", "files", "List of regexes for files to exclude from coverage.", aliases = List("--coverage-exclude-files"))
 
   /* Other settings */
   val encoding: Setting[String] = StringSetting("-encoding", "encoding", "Specify character encoding used by source files.", Properties.sourceEncoding, aliases = List("--encoding"))

compiler/src/dotty/tools/dotc/transform/InstrumentCoverage.scala

@@ -13,12 +13,15 @@ import core.Constants.Constant
 import core.NameOps.isContextFunction
 import core.StdNames.nme
 import core.Types.*
+import core.Decorators.*
 import coverage.*
 import typer.LiftCoverage
 import util.{SourcePosition, SourceFile}
 import util.Spans.Span
 import localopt.StringInterpolatorOpt
 import inlines.Inlines
+import scala.util.matching.Regex
+import java.util.regex.Pattern
 
 /** Implements code coverage by inserting calls to scala.runtime.coverage.Invoker
   * ("instruments" the source code).
@@ -41,6 +44,9 @@ class InstrumentCoverage extends MacroTransform with IdentityDenotTransformer:
   // stores all instrumented statements
   private val coverage = Coverage()
 
+  private var coverageExcludeClasslikePatterns: List[Pattern] = Nil
+  private var coverageExcludeFilePatterns: List[Pattern] = Nil
+
   override def run(using ctx: Context): Unit =
     val outputPath = ctx.settings.coverageOutputDir.value
 
@@ -54,10 +60,26 @@ class InstrumentCoverage extends MacroTransform with IdentityDenotTransformer:
         .filter(_.nn.getName.nn.startsWith("scoverage"))
         .foreach(_.nn.delete())
     end if
+
+    coverageExcludeClasslikePatterns = ctx.settings.coverageExcludeClasslikes.value.map(_.r.pattern)
+    coverageExcludeFilePatterns = ctx.settings.coverageExcludeFiles.value.map(_.r.pattern)
+
     super.run
 
     Serializer.serialize(coverage, outputPath, ctx.settings.sourceroot.value)
 
+  private def isClassIncluded(sym: Symbol)(using Context): Boolean =
+    val fqn = sym.fullName.toText(ctx.printerFn(ctx)).show
+    coverageExcludeClasslikePatterns.isEmpty || !coverageExcludeClasslikePatterns.exists(
+      _.matcher(fqn).nn.matches
+    )
+
+  private def isFileIncluded(file: SourceFile)(using Context): Boolean =
+    val normalizedPath = file.path.replace(".scala", "")
+    coverageExcludeFilePatterns.isEmpty || !coverageExcludeFilePatterns.exists(
+      _.matcher(normalizedPath).nn.matches
+    )
+
   override protected def newTransformer(using Context) =
     CoverageTransformer(ctx.settings.coverageOutputDir.value)
 
@@ -269,8 +291,17 @@ class InstrumentCoverage extends MacroTransform with IdentityDenotTransformer:
             transformDefDef(tree)
 
           case tree: PackageDef =>
-            // only transform the statements of the package
-            cpy.PackageDef(tree)(tree.pid, transform(tree.stats))
+            if isFileIncluded(tree.srcPos.sourcePos.source) && isClassIncluded(tree.symbol) then
+              // only transform the statements of the package
+              cpy.PackageDef(tree)(tree.pid, transform(tree.stats))
+            else
+              tree
+
+          case tree: TypeDef =>
+            if isFileIncluded(tree.srcPos.sourcePos.source) && isClassIncluded(tree.symbol) then
+              super.transform(tree)
+            else
+              tree
 
           case tree: Assign =>
             // only transform the rhs

tests/coverage/pos/ExcludeClass.scala

@@ -0,0 +1,19 @@
+//> using options -coverage-exclude-classlikes:covtest.Klass
+
+package covtest
+
+class Klass {
+  def abs(i: Int) =
+    if i > 0 then
+      i
+    else
+      -i
+}
+
+class Klass2 {
+  def abs(i: Int) =
+    if i > 0 then
+      i
+    else
+      -i
+}

tests/coverage/pos/ExcludeClass.scoverage.check

@@ -0,0 +1,71 @@
+# Coverage data, format version: 3.0
+# Statement data:
+# - id
+# - source path
+# - package name
+# - class name
+# - class type (Class, Object or Trait)
+# - full class name
+# - method name
+# - start offset
+# - end offset
+# - line number
+# - symbol name
+# - tree name
+# - is branch
+# - invocations count
+# - is ignored
+# - description (can be multi-line)
+# '' sign
+# ------------------------------------------
+0
+ExcludeClass.scala
+covtest
+Klass2
+Class
+covtest.Klass2
+abs
+219
+220
+16
+i
+Ident
+true
+0
+false
+i
+
+1
+ExcludeClass.scala
+covtest
+Klass2
+Class
+covtest.Klass2
+abs
+236
+238
+18
+unary_-
+Select
+true
+0
+false
+-i
+
+2
+ExcludeClass.scala
+covtest
+Klass2
+Class
+covtest.Klass2
+abs
+177
+184
+14
+abs
+DefDef
+false
+0
+false
+def abs
+

tests/coverage/pos/ExcludeDef.scala

@@ -0,0 +1,9 @@
+//> using options -coverage-exclude-classlikes:covtest\..*
+
+package covtest
+
+def abs(i: Int) =
+  if i > 0 then
+    i
+  else
+    -i

tests/coverage/pos/ExcludeDef.scoverage.check

@@ -0,0 +1,20 @@
+# Coverage data, format version: 3.0
+# Statement data:
+# - id
+# - source path
+# - package name
+# - class name
+# - class type (Class, Object or Trait)
+# - full class name
+# - method name
+# - start offset
+# - end offset
+# - line number
+# - symbol name
+# - tree name
+# - is branch
+# - invocations count
+# - is ignored
+# - description (can be multi-line)
+# '' sign
+# ------------------------------------------

tests/coverage/pos/ExcludeFile.scala

@@ -0,0 +1,11 @@
+//> using options -coverage-exclude-files:.*ExcludeFile
+
+package covtest
+
+class Klass {
+  def abs(i: Int) =
+    if i > 0 then
+      i
+    else
+      -i
+}

tests/coverage/pos/ExcludeFile.scoverage.check

@@ -0,0 +1,20 @@
+# Coverage data, format version: 3.0
+# Statement data:
+# - id
+# - source path
+# - package name
+# - class name
+# - class type (Class, Object or Trait)
+# - full class name
+# - method name
+# - start offset
+# - end offset
+# - line number
+# - symbol name
+# - tree name
+# - is branch
+# - invocations count
+# - is ignored
+# - description (can be multi-line)
+# '' sign
+# ------------------------------------------

tests/coverage/pos/ExcludeOtherStuff.scala

@@ -0,0 +1,15 @@
+//> using options -coverage-exclude-classlikes:covtest.Oject,covtest.Tait
+
+package covtest
+
+object Oject {
+  def abs(i: Int) =
+    if i > 0 then
+      i
+    else
+      -i
+}
+
+trait Tait {
+  def abs(i: Int): Int
+}

tests/coverage/pos/ExcludeOtherStuff.scoverage.check

@@ -0,0 +1,20 @@
+# Coverage data, format version: 3.0
+# Statement data:
+# - id
+# - source path
+# - package name
+# - class name
+# - class type (Class, Object or Trait)
+# - full class name
+# - method name
+# - start offset
+# - end offset
+# - line number
+# - symbol name
+# - tree name
+# - is branch
+# - invocations count
+# - is ignored
+# - description (can be multi-line)
+# '' sign
+# ------------------------------------------

tests/coverage/pos/ExcludePackage.scala

@@ -0,0 +1,11 @@
+//> using options -coverage-exclude-classlikes:covtest
+
+package covtest
+
+class Klass {
+  def abs(i: Int) =
+    if i > 0 then
+      i
+    else
+      -i
+}

tests/coverage/pos/ExcludePackage.scoverage.check

@@ -0,0 +1,20 @@
+# Coverage data, format version: 3.0
+# Statement data:
+# - id
+# - source path
+# - package name
+# - class name
+# - class type (Class, Object or Trait)
+# - full class name
+# - method name
+# - start offset
+# - end offset
+# - line number
+# - symbol name
+# - tree name
+# - is branch
+# - invocations count
+# - is ignored
+# - description (can be multi-line)
+# '' sign
+# ------------------------------------------