From c66f0d7f1e743167295d10779fa2674f69c4ae89 Mon Sep 17 00:00:00 2001
From: mautamu <mautam@usa.com>
Date: Wed, 28 Apr 2021 21:26:39 -0500
Subject: [PATCH 1/3] Add some tests to cargo/test.md. Partially addresses
 #1304

---
 src/cargo/test.md | 85 +++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 82 insertions(+), 3 deletions(-)

diff --git a/src/cargo/test.md b/src/cargo/test.md
index b4bc69d5c5..27f265278d 100644
--- a/src/cargo/test.md
+++ b/src/cargo/test.md
@@ -14,12 +14,19 @@ foo
 ├── Cargo.toml
 ├── src
 │   └── main.rs
+│   └── lib.rs
 └── tests
     ├── my_test.rs
     └── my_other_test.rs
 ```
 
-Each file in `tests` is a separate integration test.
+Each file in `tests` is a separate 
+[integration test](https://doc.rust-lang.org/book/ch11-03-test-organization.html#integration-tests),
+i.e. a test that is meant to test your library as if it were being called from a dependent
+crate.
+
+The [Testing](testing.md) chapter elaborates on the three different testing styles: 
+[Unit](testing/unit_testing.md), [Doc](testing/doc_testing.md), and [Integration](testing/integration_testing.md). 
 
 `cargo` naturally provides an easy way to run all of your tests!
 
@@ -64,5 +71,77 @@ test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 2 filtered out
 ```
 
 One word of caution: Cargo may run multiple tests concurrently, so make sure
-that they don't race with each other. For example, if they all output to a
-file, you should make them write to different files.
+that they don't race with each other. 
+
+One example of this concurrency causing issues is if two tests output to a
+file, such as below:
+
+```rust
+#[cfg(test)]
+mod tests {
+    // Import the necessary modules
+    use std::fs::OpenOptions;
+    use std::io::Write;
+
+    // This test writes to a file
+    #[test]
+    fn test_file() {
+        // Opens the file ferris.txt or creates one if it doesn't exist.
+        let mut file = OpenOptions::new()
+            .append(true)
+            .create(true)
+            .open("ferris.txt")
+            .expect("Failed to open ferris.txt");
+
+        // Print "Ferris" 5 times.
+        for _ in 0..5 {
+            file.write_all("Ferris\n".as_bytes())
+                .expect("Could not write to ferris.txt");
+        }
+    }
+
+    // This test tries to write to the same file
+    #[test]
+    fn test_file_also() {
+        // Opens the file ferris.txt or creates one if it doesn't exist.
+        let mut file = OpenOptions::new()
+            .append(true)
+            .create(true)
+            .open("ferris.txt")
+            .expect("Failed to open ferris.txt");
+
+        // Print "Corro" 5 times.
+        for _ in 0..5 {
+            file.write_all("Corro\n".as_bytes())
+                .expect("Could not write to ferris.txt");
+        }
+    }
+}
+```
+
+Although the intent is to get the following:
+```
+Ferris
+Ferris
+Ferris
+Ferris
+Ferris
+Corro
+Corro
+Corro
+Corro
+Corro
+```
+What actually gets put into `ferris.txt` is this:
+```
+Corro
+Ferris
+Corro
+Ferris
+Corro
+Ferris
+Corro
+Ferris
+Corro
+Ferris
+```

From cb9e82723f77ad81aaee0cd067c2e64af72f10cd Mon Sep 17 00:00:00 2001
From: mautamu <mautam@usa.com>
Date: Wed, 28 Apr 2021 22:09:05 -0500
Subject: [PATCH 2/3] Fix mistake in codeblock definitions

---
 src/cargo/test.md | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/cargo/test.md b/src/cargo/test.md
index 27f265278d..e28c200659 100644
--- a/src/cargo/test.md
+++ b/src/cargo/test.md
@@ -120,7 +120,8 @@ mod tests {
 ```
 
 Although the intent is to get the following:
-```
+```shell
+$ cat ferris.txt
 Ferris
 Ferris
 Ferris
@@ -133,7 +134,8 @@ Corro
 Corro
 ```
 What actually gets put into `ferris.txt` is this:
-```
+```shell
+$ cargo test test_foo
 Corro
 Ferris
 Corro

From fb8b522b8c2ee0b770cd09cfaef9b660140ffd4c Mon Sep 17 00:00:00 2001
From: mautamu <mautam@usa.com>
Date: Wed, 28 Apr 2021 23:51:15 -0500
Subject: [PATCH 3/3] Fix broken link mistake

---
 src/cargo/test.md | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/cargo/test.md b/src/cargo/test.md
index e28c200659..01884a09af 100644
--- a/src/cargo/test.md
+++ b/src/cargo/test.md
@@ -25,8 +25,8 @@ Each file in `tests` is a separate
 i.e. a test that is meant to test your library as if it were being called from a dependent
 crate.
 
-The [Testing](testing.md) chapter elaborates on the three different testing styles: 
-[Unit](testing/unit_testing.md), [Doc](testing/doc_testing.md), and [Integration](testing/integration_testing.md). 
+The [Testing][testing] chapter elaborates on the three different testing styles: 
+[Unit][unit_testing], [Doc][doc_testing], and [Integration][integration_testing]. 
 
 `cargo` naturally provides an easy way to run all of your tests!
 
@@ -147,3 +147,8 @@ Ferris
 Corro
 Ferris
 ```
+
+[testing]: ../testing.md
+[unit_testing]: ../testing/unit_testing.md
+[integration_testing]: ../testing/unit_testing.md
+[doc_testing]: ../testing/doc_testing.md