plugins/devkit/devkit-java-tests/testData/codeInsight/extensionPointNameValidity.xml

<idea-plugin>
  <id>foo</id>
  <vendor>JetBrains</vendor>
  <version>1.0</version>

  <extensionPoints>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'Smth', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">Smth</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name '.smth', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">.smth</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'smth.', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">smth.</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'SMTH', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">SMTH</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name '.', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">.</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'sm_th', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">sm_th</weak_warning>"/>

    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'sm.Th', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">sm.Th</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'Sm.th', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">Sm.th</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'Sm.Th', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">Sm.Th</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'sm.th.SmTh', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">sm.th.SmTh</weak_warning>"/>
    <extensionPoint interface="java.lang.Runnable" name="<weak_warning descr="Invalid EP name 'sm.th.Sm111', must contain only latin characters, digits and dots, must not start/end with dot, each fragment must start with lowercase character, last fragment words must not repeat any previous fragment">sm.th.Sm111</weak_warning>"/>

    <extensionPoint interface="java.lang.Runnable" name="smth"/>
    <extensionPoint interface="java.lang.Runnable" name="sm.th"/>
    <extensionPoint interface="java.lang.Runnable" name="sm1th"/>
    <extensionPoint interface="java.lang.Runnable" name="smth2"/>
  </extensionPoints>
</idea-plugin>