Turn devenv into a library

This is a small example of how to turn the devenv binary into both a
library and a binary. The reason this works is that the
devenv/Cargo.toml file would allow you to specify one or more binaries,
and only a single library. However, because we are using the default
values for everything, we do not need to explicitly define these
sections. The library entry point will be devenv/src/lib.rs.

In the lib.rs file, we specify that we also want to use the log module.
So we define and export this module. So now anything that imports the
devenv package can just use devenv::log::* in order to access the pieces
defined inside of that module.

There is a problem including the command module since main.rs defines an
App struct, and then the command module defines an implementation of
that struct. The problem here being that lib.rs does not define the App
struct, so when the command module has use crate::App, it is not defined
as it is in the case of the devenv binary.

Cargo.toml

@@ -3,5 +3,4 @@ resolver = "2"
 members = [
     "devenv",
     "devenv-run-tests",
-    "devenv_core",
 ]

devenv-run-tests/Cargo.toml

@@ -6,4 +6,4 @@ edition = "2018"
 [dependencies]
 clap = { version = "3", features = ["derive"] }
 
-devenv_core = { path = "../devenv_core" }
+devenv= { path = "../devenv" }

devenv-run-tests/src/main.rs

@@ -1,4 +1,6 @@
 use clap::Parser;
+use devenv::log::Level;
+use devenv::log::Logger;
 use std::fs;
 use std::path::PathBuf;
 
@@ -30,6 +32,10 @@ struct TestResult {
 }
 
 fn run_tests_in_directory(args: &Args) -> Result<Vec<TestResult>, Box<dyn std::error::Error>> {
+    let logger = Logger::new(Level::Info);
+
+    logger.info("Running Tests");
+
     let cwd = std::env::current_dir()?;
     let cwd = cwd.display();
 

devenv/Cargo.toml

@@ -28,5 +28,4 @@ which = "6.0.0"
 whoami = "1.5.1"
 xdg = "2.5.2"
 
-devenv_core = { path = "../devenv_core" }
 schemars = "0.8.16"

devenv/src/lib.rs

@@ -0,0 +1 @@
+pub mod log;

package.nix

@@ -9,7 +9,6 @@ pkgs.rustPlatform.buildRustPackage {
     "Cargo.lock"
     "devenv(/\.*)?"
     "devenv-run-tests(/\.*)?"
-    "devenv_core(/\.*)?"
   ];
 
   cargoLock = {