Merged tests to produce a single binary (#12826)

This PR should close #7147 

# Description
Merged src/tests into /tests to produce a single binary.

![image](https://github.com/nushell/nushell/assets/94604837/84726469-d447-4619-b6d1-2d1415d0f42e)

# User-Facing Changes
No user facing changes

# Tests + Formatting
Moved tests. Tollkit check pr pass.

# After Submitting

---------

Co-authored-by: Ian Manske <ian.manske@pm.me>

tests/repl/tests.rs

@@ -0,0 +1,164 @@
+use assert_cmd::prelude::*;
+use pretty_assertions::assert_eq;
+use std::collections::HashMap;
+use std::io::Write;
+use std::process::Command;
+use tempfile::NamedTempFile;
+
+pub type TestResult = Result<(), Box<dyn std::error::Error>>;
+
+pub fn run_test_with_env(input: &str, expected: &str, env: &HashMap<&str, &str>) -> TestResult {
+    let mut file = NamedTempFile::new()?;
+    let name = file.path();
+
+    let mut cmd = Command::cargo_bin("nu")?;
+    cmd.arg("--no-config-file");
+    cmd.arg(name).envs(env);
+
+    writeln!(file, "{input}")?;
+
+    run_cmd_and_assert(cmd, expected)
+}
+
+#[cfg(test)]
+pub fn run_test(input: &str, expected: &str) -> TestResult {
+    let mut file = NamedTempFile::new()?;
+    let name = file.path();
+
+    let mut cmd = Command::cargo_bin("nu")?;
+    cmd.arg("--no-std-lib");
+    cmd.arg("--no-config-file");
+    cmd.arg(name);
+    cmd.env(
+        "PWD",
+        std::env::current_dir().expect("Can't get current dir"),
+    );
+
+    writeln!(file, "{input}")?;
+
+    run_cmd_and_assert(cmd, expected)
+}
+
+#[cfg(test)]
+pub fn run_test_std(input: &str, expected: &str) -> TestResult {
+    let mut file = NamedTempFile::new()?;
+    let name = file.path();
+
+    let mut cmd = Command::cargo_bin("nu")?;
+    cmd.arg("--no-config-file");
+    cmd.arg(name);
+    cmd.env(
+        "PWD",
+        std::env::current_dir().expect("Can't get current dir"),
+    );
+
+    writeln!(file, "{input}")?;
+
+    run_cmd_and_assert(cmd, expected)
+}
+
+#[cfg(test)]
+fn run_cmd_and_assert(mut cmd: Command, expected: &str) -> TestResult {
+    let output = cmd.output()?;
+
+    let stderr = String::from_utf8_lossy(&output.stderr).to_string();
+    let stdout = String::from_utf8_lossy(&output.stdout).to_string();
+
+    println!("stdout: {stdout}");
+    println!("stderr: {stderr}");
+
+    assert!(output.status.success());
+
+    assert_eq!(stdout.trim(), expected);
+
+    Ok(())
+}
+
+#[cfg(test)]
+pub fn run_test_contains(input: &str, expected: &str) -> TestResult {
+    let mut file = NamedTempFile::new()?;
+    let name = file.path();
+
+    let mut cmd = Command::cargo_bin("nu")?;
+    cmd.arg("--no-std-lib");
+    cmd.arg("--no-config-file");
+    cmd.arg(name);
+
+    writeln!(file, "{input}")?;
+
+    let output = cmd.output()?;
+
+    let stderr = String::from_utf8_lossy(&output.stderr).to_string();
+    let stdout = String::from_utf8_lossy(&output.stdout).to_string();
+
+    println!("stdout: {stdout}");
+    println!("stderr: {stderr}");
+
+    println!("Expected output to contain: {expected}");
+    assert!(output.status.success());
+
+    assert!(stdout.contains(expected));
+
+    Ok(())
+}
+
+#[cfg(test)]
+pub fn test_ide_contains(input: &str, ide_commands: &[&str], expected: &str) -> TestResult {
+    let mut file = NamedTempFile::new()?;
+    let name = file.path();
+
+    let mut cmd = Command::cargo_bin("nu")?;
+    cmd.arg("--no-std-lib");
+    cmd.arg("--no-config-file");
+    for ide_command in ide_commands {
+        cmd.arg(ide_command);
+    }
+    cmd.arg(name);
+
+    writeln!(file, "{input}")?;
+
+    let output = cmd.output()?;
+
+    let stderr = String::from_utf8_lossy(&output.stderr).to_string();
+    let stdout = String::from_utf8_lossy(&output.stdout).to_string();
+
+    println!("stdout: {stdout}");
+    println!("stderr: {stderr}");
+    println!("Expected output to contain: {expected}");
+
+    assert!(output.status.success());
+
+    assert!(stdout.contains(expected));
+
+    Ok(())
+}
+
+#[cfg(test)]
+pub fn fail_test(input: &str, expected: &str) -> TestResult {
+    let mut file = NamedTempFile::new()?;
+    let name = file.path();
+
+    let mut cmd = Command::cargo_bin("nu")?;
+    cmd.arg("--no-std-lib");
+    cmd.arg("--no-config-file");
+    cmd.arg(name);
+    cmd.env(
+        "PWD",
+        std::env::current_dir().expect("Can't get current dir"),
+    );
+
+    writeln!(file, "{input}")?;
+
+    let output = cmd.output()?;
+
+    let stderr = String::from_utf8_lossy(&output.stderr).to_string();
+    let stdout = String::from_utf8_lossy(&output.stdout).to_string();
+
+    println!("stdout: {stdout}");
+    println!("stderr: {stderr}");
+    println!("Expected error to contain: {expected}");
+
+    assert!(!stderr.is_empty() && stderr.contains(expected));
+
+    Ok(())
+}