Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Project: replace JavaParser by javac #6678

Merged
merged 1 commit into from
Jun 25, 2024
Merged

Project: replace JavaParser by javac #6678

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
45 changes: 26 additions & 19 deletions docs/developer/new-contributor-projects.html
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -51,6 +51,7 @@ <h1>Projects for new contributors</h1> <!-- omit from toc -->
<ul>
<li><a href="#hint-about-annotated-library-methods">Indicate library methods that should be used instead</a></li>
<li><a href="#index-errors">Improving error messages</a></li>
<li><a href="#javaparser-to-javac-parse">Replace JavaParser by javac</a></li>
<li><a href="#java-expression-parser">Java expression parser</a></li>
<li><a href="#dataflow">Dataflow enhancements</a></li>
<li><a href="#Purity_analysis">Side effect analysis, also known as purity analysis</a></li>
Expand Down Expand Up @@ -1343,25 +1344,31 @@ <h2 id="index-errors">Improving error messages</h2>
</ul>


<h2 id="javaparser-to-javac-parse">Replace JavaParser by javac</h2>

<p>
The Checker Framework uses JavaParser to parse
<a href="https://checkerframework.org/manual/#java-expressions-as-arguments">a
Java expressions</a>. However, JavaParser is buggy and poorly maintained.
The goal of this project is to replace every use of JavaParser by a use of
<a href="https://github.com/plume-lib/javac-parse">javac-parse</a>.
</p>


<h2 id="java-expression-parser">Java expression parser</h2>

<p>
A number of type annotations take, as an
argument, <a href="https://checkerframework.org/manual/#java-expressions-as-arguments">a
Java expression</a>. The representation for these
(the <a href="https://checkerframework.org/api/org/checkerframework/dataflow/expression/JavaExpression.html"><code>JavaExpression</code></a>
class) is a hack. The goal of this
project is to remove it.
Java expression</a>. The representation for these is as a <a href="https://checkerframework.org/api/org/checkerframework/dataflow/expression/JavaExpression.html"><code>JavaExpression</code></a>. The goal of this
project is to remove it.
</p>

<p>
The <code>JavaExpression</code> class
represents an AST. There is no need for the Checker Framework to
define its own AST when the JavaParser AST already exists and is
maintained. In fact, <code>JavaExpressionParseUtil</code> uses JavaParser,
but needlessly converts a
JavaParser <code>Expression</code> into
a <code>JavaExpression</code>.
define its own AST when the javac AST already exists and is
maintained.
</p>

<p>
Expand All @@ -1371,29 +1378,29 @@ <h2 id="java-expression-parser">Java expression parser</h2>
<li>
Replace every use
of <a href="https://checkerframework.org/api/org/checkerframework/dataflow/expression/JavaExpression.html"><code>JavaExpression</code></a>
by a use of the JavaParser
class <a href="https://www.javadoc.io/static/com.github.javaparser/javaparser-core/3.15.22/com/github/javaparser/ast/expr/Expression.html"><code>com.github.javaparser.ast.expr.Expression</code></a>.
by a use of the javac class
class <a href="https://www.javadoc.io/static/org.kohsuke.sorcerer/sorcerer-javac/0.11/com/sun/tools/javac/tree/JCTree.JCExpression.html"><code>com.sun.tools.javac.tree.JCTree.JCExpression.html</code></a>.
</li>
<li>
Replace every use of a subclass of <code>JavaExpression</code> (listed in the
"Direct Known Subclasses" section of
the <a href="https://checkerframework.org/api/org/checkerframework/dataflow/expression/JavaExpression.html"><code>JavaExpression</code>
API documentation)</a> by a use of a
<a href="https://www.javadoc.io/static/com.github.javaparser/javaparser-core/3.15.22/com/github/javaparser/ast/expr/Expression.html">subclass of <code>Expression</code></a>. For example, replace every use
of <a href="https://checkerframework.org/api/org/checkerframework/dataflow/expression/MethodCall.html"><code>MethodCall</code></a> by <a href="https://www.javadoc.io/static/com.github.javaparser/javaparser-core/3.15.22/com/github/javaparser/ast/expr/MethodCallExpr.html"><code>MethodCallExpr</code></a>.
<a href="https://www.javadoc.io/static/org.kohsuke.sorcerer/sorcerer-javac/0.11/com/sun/tools/javac/tree/JCTree.JCExpression.html">subclass
of <code>JCTree.JCExpression.html</code></a>.
For example, replace every use
of <a href="https://checkerframework.org/api/org/checkerframework/dataflow/expression/MethodCall.html"><code>MethodCall</code></a> by <a href="https://www.javadoc.io/static/org.kohsuke.sorcerer/sorcerer-javac/0.11/com/sun/tools/javac/tree/JCTree.JCMethodInvocation.html"><code>JCTree.JCMethodInvocation</code></a>.
</li>
<li>
The <a href="https://checkerframework.org/api/org/checkerframework/framework/util/JavaExpressionParseUtil.html"><code>JavaExpressionParseUtil</code></a>
class already uses JavaParser, but it uses <code>ExpressionToReceiverVisitor</code> to construct
a <code>JavaExpression</code>. Have it return a
JavaParser <code>Expression</code> instead, and delete <code>ExpressionToReceiverVisitor</code>.
Replace the <a href="https://checkerframework.org/api/org/checkerframework/framework/util/JavaExpressionParseUtil.html"><code>JavaExpressionParseUtil</code></a>
class and delete <code>ExpressionToReceiverVisitor</code>.
</li>
</ul>

<p>
Direct replacement of the classes is not possible, or we would have done it
already. For example, <code>JavaExpression</code> contains some methods that
JavaParser lacks, such as <code>isUnassignableByOtherCode</code>. As a
javac lacks, such as <code>isUnassignableByOtherCode</code>. As a
first step before doing the tasks listed above, you may want to convert
these methods from instance methods of <code>JavaExpression</code> into static
methods in <code>JavaExpressions</code>, making <code>JavaExpression</code> more
Expand All @@ -1403,7 +1410,7 @@ <h2 id="java-expression-parser">Java expression parser</h2>
An
alternate design (or a partial step in the refactoring process) would be to
retain the <code>JavaExpression</code> class, but make it a thin wrapper around
JavaParser classes that do most of the real work.
javac classes that do most of the real work.
</p>

<p>
Expand Down