From 5cb5ee026c67ab7f0eb59040224bb63c4206d067 Mon Sep 17 00:00:00 2001
From: Chris Smowton <smowton@github.com>
Date: Fri, 22 Mar 2024 20:51:10 +0000
Subject: [PATCH] Fix pretty-printing of anonymous vars and multiple patterns;
 add test

---
 java/ql/lib/semmle/code/java/PrettyPrintAst.qll    | 14 ++++++++++----
 java/ql/test/library-tests/prettyprint/Test.java   |  7 +++++++
 java/ql/test/library-tests/prettyprint/options     |  2 +-
 java/ql/test/library-tests/prettyprint/pp.expected | 10 ++++++++--
 4 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/java/ql/lib/semmle/code/java/PrettyPrintAst.qll b/java/ql/lib/semmle/code/java/PrettyPrintAst.qll
index b91d371b187..36f5ce1ed89 100644
--- a/java/ql/lib/semmle/code/java/PrettyPrintAst.qll
+++ b/java/ql/lib/semmle/code/java/PrettyPrintAst.qll
@@ -400,7 +400,8 @@ private class PpInstanceOfExpr extends PpAst, InstanceOfExpr {
 
 private class PpLocalVariableDeclExpr extends PpAst, LocalVariableDeclExpr {
   override string getPart(int i) {
-    i = 0 and result = this.getName()
+    i = 0 and
+    (if this.isAnonymous() then result = "_" else result = this.getName())
     or
     i = 1 and result = " = " and exists(this.getInit())
   }
@@ -793,7 +794,11 @@ private class PpPatternCase extends PpAst, PatternCase {
       or
       i = base + 2 and
       this.getPatternAtIndex(n) instanceof LocalVariableDeclExpr and
-      not this.isAnonymousPattern(n) and
+      (
+        exists(this.getPatternAtIndex(n).asBindingOrUnnamedPattern().getTypeAccess())
+        or
+        not this.isAnonymousPattern(n)
+      ) and
       result = " "
       or
       i = base + 3 and
@@ -815,9 +820,10 @@ private class PpPatternCase extends PpAst, PatternCase {
 
   override PpAst getChild(int i) {
     exists(int n, int base | exists(this.getPatternAtIndex(n)) and base = n * 4 |
-      i = 1 and result = this.getPatternAtIndex(n).asBindingOrUnnamedPattern().getTypeAccess()
+      i = base + 1 and
+      result = this.getPatternAtIndex(n).asBindingOrUnnamedPattern().getTypeAccess()
       or
-      i = 1 and result = this.getPatternAtIndex(n).asRecordPattern()
+      i = base + 1 and result = this.getPatternAtIndex(n).asRecordPattern()
     )
     or
     exists(int base | base = (max(int n | exists(this.getPatternAtIndex(n))) + 1) * 4 |
diff --git a/java/ql/test/library-tests/prettyprint/Test.java b/java/ql/test/library-tests/prettyprint/Test.java
index c643955751e..1ffb1671459 100644
--- a/java/ql/test/library-tests/prettyprint/Test.java
+++ b/java/ql/test/library-tests/prettyprint/Test.java
@@ -45,6 +45,13 @@ public class Test {
 
     if (o instanceof R(S(var x), var y)) { }
 
+    switch(o) {
+      case String _, Integer _:
+      case R(S(_), _):
+      default:
+        break;
+    }
+
   }
 
 }
diff --git a/java/ql/test/library-tests/prettyprint/options b/java/ql/test/library-tests/prettyprint/options
index a0d1b7e7002..5011824a5d7 100644
--- a/java/ql/test/library-tests/prettyprint/options
+++ b/java/ql/test/library-tests/prettyprint/options
@@ -1 +1 @@
-//semmle-extractor-options: --javac-args --release 21
+//semmle-extractor-options: --javac-args --release 22
diff --git a/java/ql/test/library-tests/prettyprint/pp.expected b/java/ql/test/library-tests/prettyprint/pp.expected
index eb4fbaf0633..fb9608f8f41 100644
--- a/java/ql/test/library-tests/prettyprint/pp.expected
+++ b/java/ql/test/library-tests/prettyprint/pp.expected
@@ -84,5 +84,11 @@
 | Test.java:1:14:1:17 | Test | 83 |     } |
 | Test.java:1:14:1:17 | Test | 84 |     if (o instanceof R(S(var x), var y)) { |
 | Test.java:1:14:1:17 | Test | 85 |     } |
-| Test.java:1:14:1:17 | Test | 86 |   } |
-| Test.java:1:14:1:17 | Test | 87 | } |
+| Test.java:1:14:1:17 | Test | 86 |     switch (o) { |
+| Test.java:1:14:1:17 | Test | 87 |       case String _, Integer _: |
+| Test.java:1:14:1:17 | Test | 88 |       case R(S(var _), var _): |
+| Test.java:1:14:1:17 | Test | 89 |       default: |
+| Test.java:1:14:1:17 | Test | 90 |       break; |
+| Test.java:1:14:1:17 | Test | 91 |     } |
+| Test.java:1:14:1:17 | Test | 92 |   } |
+| Test.java:1:14:1:17 | Test | 93 | } |