From a433a9067386802147354413af5194f1e39ef9c9 Mon Sep 17 00:00:00 2001
From: Stephan Schroevers <stephan.schroevers@teampicnic.com>
Date: Wed, 7 Aug 2024 15:41:45 +0200
Subject: [PATCH] Introduce `FilesCreateTempFileToFile` Refaster rule (#1162)

---
 .../errorprone/refasterrules/FileRules.java   | 23 +++++++++++++++++++
 .../refasterrules/FileRulesTestInput.java     |  7 ++++++
 .../refasterrules/FileRulesTestOutput.java    |  7 ++++++
 3 files changed, 37 insertions(+)

diff --git a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/FileRules.java b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/FileRules.java
index bc230e0ae5..3a45fe1e4b 100644
--- a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/FileRules.java
+++ b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/FileRules.java
@@ -2,12 +2,15 @@
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.google.errorprone.refaster.Refaster;
 import com.google.errorprone.refaster.annotation.AfterTemplate;
 import com.google.errorprone.refaster.annotation.BeforeTemplate;
+import java.io.File;
 import java.io.IOException;
 import java.nio.charset.Charset;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.attribute.FileAttribute;
 import tech.picnic.errorprone.refaster.annotation.OnlineDocumentation;
 
 /** Refaster rules related to expressions dealing with files. */
@@ -40,4 +43,24 @@ String after(Path path) throws IOException {
       return Files.readString(path);
     }
   }
+
+  /**
+   * Prefer {@link Files#createTempFile(String, String, FileAttribute[])} over alternatives that
+   * create files with more liberal permissions.
+   */
+  static final class FilesCreateTempFileToFile {
+    @BeforeTemplate
+    @SuppressWarnings("java:S5443" /* This violation will be rewritten. */)
+    File before(String prefix, String suffix) throws IOException {
+      return Refaster.anyOf(
+          File.createTempFile(prefix, suffix), File.createTempFile(prefix, suffix, null));
+    }
+
+    @AfterTemplate
+    @SuppressWarnings(
+        "java:S5443" /* On POSIX systems the file will only have user read-write permissions. */)
+    File after(String prefix, String suffix) throws IOException {
+      return Files.createTempFile(prefix, suffix).toFile();
+    }
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestInput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestInput.java
index c33f3e679f..ea50c16e62 100644
--- a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestInput.java
+++ b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestInput.java
@@ -1,5 +1,7 @@
 package tech.picnic.errorprone.refasterrules;
 
+import com.google.common.collect.ImmutableSet;
+import java.io.File;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
@@ -14,4 +16,9 @@ String testFilesReadStringWithCharset() throws IOException {
   String testFilesReadString() throws IOException {
     return Files.readString(Paths.get("foo"), StandardCharsets.UTF_8);
   }
+
+  ImmutableSet<File> testFilesCreateTempFileToFile() throws IOException {
+    return ImmutableSet.of(
+        File.createTempFile("foo", "bar"), File.createTempFile("baz", "qux", null));
+  }
 }
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestOutput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestOutput.java
index 5b516e31f9..3494efbcff 100644
--- a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestOutput.java
+++ b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/FileRulesTestOutput.java
@@ -1,5 +1,7 @@
 package tech.picnic.errorprone.refasterrules;
 
+import com.google.common.collect.ImmutableSet;
+import java.io.File;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
@@ -14,4 +16,9 @@ String testFilesReadStringWithCharset() throws IOException {
   String testFilesReadString() throws IOException {
     return Files.readString(Paths.get("foo"));
   }
+
+  ImmutableSet<File> testFilesCreateTempFileToFile() throws IOException {
+    return ImmutableSet.of(
+        Files.createTempFile("foo", "bar").toFile(), Files.createTempFile("baz", "qux").toFile());
+  }
 }