[groovy] IDEA-251327: Add inspection for calls with implicit null

GitOrigin-RevId: 66d8c31982330f201cd08043a44752577c013b9c
2026-09-27 10:03:11 +07:00 · 2020-10-21 17:35:37 +00:00
parent b5e457fd57
commit 8f06d4fbad
4 changed files with 57 additions and 0 deletions
@@ -0,0 +1,20 @@
+<html>
+<body>
+Reports calls with no arguments to method that has exactly one parameter.
+This is equivalent to call with <code>null</code>, and that behavior is often confusing and unintended.
+<br>
+Example:
+<br>
+<pre>
+    def foo(String s){}
+
+    foo()
+</pre>
+Will be executed as following:
+<pre>
+    def foo(String s){}
+
+    foo(<b>null</b>)
+</pre>
+</body>
+</html>
@@ -538,6 +538,7 @@ inspection.display.name.check.labeled.statement=Labeled statement inspection
 inspection.display.name.variable.can.be.final=Variable can be final
 inspection.display.name.equals.between.inconvertible.types='equals()' between objects of inconvertible types
 inspection.display.name.singleton.constructor=@Singleton constructors
+inspection.display.name.implicit.null.argument=Implicit null argument
 inspection.message.access.to.static.field.locked.on.instance.data=Access to static field <code>#ref</code> locked on instance data #loc
 inspection.message.assignment.replaceable.with.operator.assignment=<code>#ref</code> could be simplified to ''{0}'' #loc
 inspection.message.assignment.to.for.loop.parameter=Assignment to for-loop parameter '#ref' #loc
@@ -638,6 +639,7 @@ inspection.message.unused.catch.parameter.ref=Unused catch parameter '#ref' #loc
 inspection.message.package.name.mismatch.actual.0.expected.1=Package name mismatch. Actual: ''{0}'', expected: ''{1}''
 inspection.message.property.not.indexable.type.must.be.array.or.list.but.found.0=Property is not indexable. Type must be array or list but found {0}
 inspection.message.type.argument.0.can.not.be.1=Type of argument ''{0}'' can not be ''{1}''
+inspection.message.method.called.with.implicit.null.argument=Method is called with implicit null argument
 text.class.0.is.unused=Class {0} is unused
 text.constructor.0.is.unused=Constructor {0} is unused
 text.method.0.is.unused=Method {0} is unused
@@ -0,0 +1,31 @@
+// Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package org.jetbrains.plugins.groovy.codeInspection.confusing
+
+import com.intellij.codeInspection.ProblemHighlightType
+import com.intellij.psi.util.parentOfType
+import org.jetbrains.plugins.groovy.GroovyBundle
+import org.jetbrains.plugins.groovy.codeInspection.BaseInspection
+import org.jetbrains.plugins.groovy.codeInspection.BaseInspectionVisitor
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.arguments.GrArgumentList
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.expressions.GrCall
+import org.jetbrains.plugins.groovy.lang.psi.util.PsiUtil
+
+class GroovyImplicitNullArgumentCallInspection : BaseInspection() {
+
+  override fun buildErrorString(vararg args: Any?): String {
+    return GroovyBundle.message("inspection.message.method.called.with.implicit.null.argument")
+  }
+
+  override fun buildVisitor(): BaseInspectionVisitor = object : BaseInspectionVisitor() {
+    override fun visitArgumentList(list: GrArgumentList) {
+      if (list.allArguments.isNotEmpty()) {
+        return
+      }
+      val call = list.parentOfType<GrCall>()?.takeIf { it.argumentList === list } ?: return
+      if (PsiUtil.isEligibleForInvocationWithNull(call)) {
+        registerError(list, ProblemHighlightType.WEAK_WARNING)
+      }
+      super.visitArgumentList(list)
+    }
+  }
+}
@@ -1075,6 +1075,10 @@
                     groupKey="inspection.confusing"
                     enabledByDefault="true"
                     implementationClass="org.jetbrains.plugins.groovy.codeInspection.confusing.GroovyGStringKeyInspection"/>
+    <localInspection language="Groovy" groupPath="Groovy" key="inspection.display.name.implicit.null.argument"
+                     groupKey="inspection.confusing"
+                     enabledByDefault="true"
+                     implementationClass="org.jetbrains.plugins.groovy.codeInspection.confusing.GroovyImplicitNullArgumentCallInspection"/>
    <localInspection language="Groovy" groupPath="Groovy" key="inspection.display.name.duplicate.switch.branch"
                     groupKey="inspection.validity"
                     enabledByDefault="true"