test: Add null tests to modules that don't have them (#1104)

Have added some null tests to modules that don't already have them.

tests/testsuite/git_branch.rs

@@ -2,9 +2,25 @@ use ansi_term::Color;
 use remove_dir_all::remove_dir_all;
 use std::io;
 use std::process::Command;
+use tempfile;
 
 use crate::common::{self, TestCommand};
 
+#[test]
+fn show_nothing_on_empty_dir() -> io::Result<()> {
+    let repo_dir = tempfile::tempdir()?;
+
+    let output = common::render_module("git_branch")
+        .arg("--path")
+        .arg(repo_dir.path())
+        .output()?;
+    let actual = String::from_utf8(output.stdout).unwrap();
+
+    let expected = "";
+    assert_eq!(expected, actual);
+    repo_dir.close()
+}
+
 #[test]
 fn test_changed_truncation_symbol() -> io::Result<()> {
     test_truncate_length_with_config(

tests/testsuite/git_commit.rs

@@ -5,6 +5,21 @@ use std::{io, str};
 
 use crate::common::{self, TestCommand};
 
+#[test]
+fn show_nothing_on_empty_dir() -> io::Result<()> {
+    let repo_dir = tempfile::tempdir()?;
+
+    let output = common::render_module("git_commit")
+        .arg("--path")
+        .arg(repo_dir.path())
+        .output()?;
+    let actual = String::from_utf8(output.stdout).unwrap();
+
+    let expected = "";
+    assert_eq!(expected, actual);
+    repo_dir.close()
+}
+
 #[test]
 fn test_render_commit_hash() -> io::Result<()> {
     let repo_dir = common::create_fixture_repo()?;

tests/testsuite/git_state.rs

@@ -5,6 +5,21 @@ use std::io::{self, Error, ErrorKind, Write};
 use std::process::{Command, Stdio};
 use tempfile;
 
+#[test]
+fn show_nothing_on_empty_dir() -> io::Result<()> {
+    let repo_dir = tempfile::tempdir()?;
+
+    let output = common::render_module("git_state")
+        .arg("--path")
+        .arg(repo_dir.path())
+        .output()?;
+    let actual = String::from_utf8(output.stdout).unwrap();
+
+    let expected = "";
+    assert_eq!(expected, actual);
+    repo_dir.close()
+}
+
 #[test]
 #[ignore]
 fn shows_rebasing() -> io::Result<()> {

tests/testsuite/git_status.rs

@@ -4,6 +4,7 @@ use std::fs::{self, File};
 use std::io;
 use std::path::PathBuf;
 use std::process::Command;
+use tempfile;
 
 use crate::common::{self, TestCommand};
 
@@ -19,6 +20,21 @@ fn barrier() {
     std::thread::sleep(std::time::Duration::from_millis(500));
 }
 
+#[test]
+fn show_nothing_on_empty_dir() -> io::Result<()> {
+    let repo_dir = tempfile::tempdir()?;
+
+    let output = common::render_module("git_status")
+        .arg("--path")
+        .arg(repo_dir.path())
+        .output()?;
+    let actual = String::from_utf8(output.stdout).unwrap();
+
+    let expected = "";
+    assert_eq!(expected, actual);
+    repo_dir.close()
+}
+
 #[test]
 #[ignore]
 fn shows_behind() -> io::Result<()> {

tests/testsuite/hg_branch.rs

@@ -16,6 +16,21 @@ enum Expect<'a> {
     TruncationSymbol(&'a str),
 }
 
+#[test]
+fn show_nothing_on_empty_dir() -> io::Result<()> {
+    let repo_dir = tempfile::tempdir()?;
+
+    let output = common::render_module("hg_branch")
+        .arg("--path")
+        .arg(repo_dir.path())
+        .output()?;
+    let actual = String::from_utf8(output.stdout).unwrap();
+
+    let expected = "";
+    assert_eq!(expected, actual);
+    repo_dir.close()
+}
+
 #[test]
 #[ignore]
 fn test_hg_get_branch_fails() -> io::Result<()> {

tests/testsuite/python.rs

@@ -6,6 +6,21 @@ use tempfile;
 
 use crate::common::{self, TestCommand};
 
+#[test]
+fn show_nothing_on_empty_dir() -> io::Result<()> {
+    let dir = tempfile::tempdir()?;
+
+    let output = common::render_module("python")
+        .arg("--path")
+        .arg(dir.path())
+        .output()?;
+    let actual = String::from_utf8(output.stdout).unwrap();
+
+    let expected = "";
+    assert_eq!(expected, actual);
+    dir.close()
+}
+
 #[test]
 #[ignore]
 fn folder_with_python_version() -> io::Result<()> {

tests/testsuite/singularity.rs

@@ -3,6 +3,15 @@ use std::io;
 
 use crate::common;
 
+#[test]
+fn no_env_set() -> io::Result<()> {
+    let output = common::render_module("singularity").output()?;
+    let actual = String::from_utf8(output.stdout).unwrap();
+
+    let expected = "";
+    assert_eq!(expected, actual);
+    Ok(())
+}
 #[test]
 fn env_set() -> io::Result<()> {
     let output = common::render_module("singularity")