feat(cli): deno init --lib (#22499)

Closes #22287

Co-authored-by: Asher Gomez <ashersaupingomez@gmail.com>
Co-authored-by: David Sherret <dsherret@gmail.com>

cli/args/flags.rs

@@ -205,6 +205,7 @@ impl FmtFlags {
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct InitFlags {
   pub dir: Option<String>,
+  pub lib: bool,
 }
 
 #[derive(Clone, Debug, Eq, PartialEq)]
@@ -2052,11 +2053,18 @@ fn init_subcommand() -> Command {
   Command::new("init")
     .about("Initialize a new project")
     .defer(|cmd| {
-      cmd.arg(
+      cmd
+        .arg(
           Arg::new("dir")
             .required(false)
             .value_hint(ValueHint::DirPath),
         )
+        .arg(
+          Arg::new("lib")
+            .long("lib")
+            .required(false)
+            .action(ArgAction::SetTrue),
+        )
     })
 }
 
@@ -4033,6 +4041,7 @@ fn fmt_parse(flags: &mut Flags, matches: &mut ArgMatches) {
 fn init_parse(flags: &mut Flags, matches: &mut ArgMatches) {
   flags.subcommand = DenoSubcommand::Init(InitFlags {
     dir: matches.remove_one::<String>("dir"),
+    lib: matches.get_flag("lib"),
   });
 }
 
@@ -9753,7 +9762,10 @@ mod tests {
     assert_eq!(
       r.unwrap(),
       Flags {
-        subcommand: DenoSubcommand::Init(InitFlags { dir: None }),
+        subcommand: DenoSubcommand::Init(InitFlags {
+          dir: None,
+          lib: false
+        }),
         ..Flags::default()
       }
     );
@@ -9764,6 +9776,7 @@ mod tests {
       Flags {
         subcommand: DenoSubcommand::Init(InitFlags {
           dir: Some(String::from("foo")),
+          lib: false
         }),
         ..Flags::default()
       }
@@ -9773,11 +9786,38 @@ mod tests {
     assert_eq!(
       r.unwrap(),
       Flags {
-        subcommand: DenoSubcommand::Init(InitFlags { dir: None }),
+        subcommand: DenoSubcommand::Init(InitFlags {
+          dir: None,
+          lib: false
+        }),
         log_level: Some(Level::Error),
         ..Flags::default()
       }
     );
+
+    let r = flags_from_vec(svec!["deno", "init", "--lib"]);
+    assert_eq!(
+      r.unwrap(),
+      Flags {
+        subcommand: DenoSubcommand::Init(InitFlags {
+          dir: None,
+          lib: true
+        }),
+        ..Flags::default()
+      }
+    );
+
+    let r = flags_from_vec(svec!["deno", "init", "foo", "--lib"]);
+    assert_eq!(
+      r.unwrap(),
+      Flags {
+        subcommand: DenoSubcommand::Init(InitFlags {
+          dir: Some(String::from("foo")),
+          lib: true
+        }),
+        ..Flags::default()
+      }
+    );
   }
 
   #[test]

cli/tools/init/mod.rs

@@ -4,10 +4,145 @@ use crate::args::InitFlags;
 use crate::colors;
 use deno_core::anyhow::Context;
 use deno_core::error::AnyError;
+use deno_core::serde_json::json;
 use log::info;
 use std::io::Write;
 use std::path::Path;
 
+pub fn init_project(init_flags: InitFlags) -> Result<(), AnyError> {
+  let cwd =
+    std::env::current_dir().context("Can't read current working directory.")?;
+  let dir = if let Some(dir) = &init_flags.dir {
+    let dir = cwd.join(dir);
+    std::fs::create_dir_all(&dir)?;
+    dir
+  } else {
+    cwd
+  };
+
+  if init_flags.lib {
+    // Extract the directory name to use as the project name
+    let project_name = dir
+      .file_name()
+      .unwrap_or_else(|| dir.as_os_str())
+      .to_str()
+      .unwrap();
+
+    create_file(
+      &dir,
+      "mod.ts",
+      r#"export function add(a: number, b: number): number {
+  return a + b;
+}
+"#,
+    )?;
+    create_file(
+      &dir,
+      "mod_test.ts",
+      r#"import { assertEquals } from "jsr:@std/assert";
+import { add } from "./mod.ts";
+
+Deno.test(function addTest() {
+  assertEquals(add(2, 3), 5);
+});
+"#,
+    )?;
+
+    create_json_file(
+      &dir,
+      "deno.json",
+      &json!({
+        "name": project_name,
+        "version": "1.0.0",
+        "exports": "./mod.ts",
+        "tasks": {
+          "dev": "deno test --watch mod.ts"
+        }
+      }),
+    )?;
+  } else {
+    create_file(
+      &dir,
+      "main.ts",
+      r#"export function add(a: number, b: number): number {
+  return a + b;
+}
+
+// Learn more at https://deno.land/manual/examples/module_metadata#concepts
+if (import.meta.main) {
+  console.log("Add 2 + 3 =", add(2, 3));
+}
+"#,
+    )?;
+    create_file(
+      &dir,
+      "main_test.ts",
+      r#"import { assertEquals } from "jsr:@std/assert";
+import { add } from "./main.ts";
+
+Deno.test(function addTest() {
+  assertEquals(add(2, 3), 5);
+});
+"#,
+    )?;
+
+    create_json_file(
+      &dir,
+      "deno.json",
+      &json!({
+        "tasks": {
+          "dev": "deno run --watch main.ts"
+        }
+      }),
+    )?;
+  }
+
+  info!("✅ {}", colors::green("Project initialized"));
+  info!("");
+  info!("{}", colors::gray("Run these commands to get started"));
+  info!("");
+  if let Some(dir) = init_flags.dir {
+    info!("  cd {}", dir);
+    info!("");
+  }
+  if init_flags.lib {
+    info!("  {}", colors::gray("# Run the tests"));
+    info!("  deno test");
+    info!("");
+    info!(
+      "  {}",
+      colors::gray("# Run the tests and watch for file changes")
+    );
+    info!("  deno task dev");
+    info!("");
+    info!("  {}", colors::gray("# Publish to JSR (dry run)"));
+    info!("  deno publish --dry-run");
+  } else {
+    info!("  {}", colors::gray("# Run the program"));
+    info!("  deno run main.ts");
+    info!("");
+    info!(
+      "  {}",
+      colors::gray("# Run the program and watch for file changes")
+    );
+    info!("  deno task dev");
+    info!("");
+    info!("  {}", colors::gray("# Run the tests"));
+    info!("  deno test");
+  }
+  Ok(())
+}
+
+fn create_json_file(
+  dir: &Path,
+  filename: &str,
+  value: &deno_core::serde_json::Value,
+) -> Result<(), AnyError> {
+  let mut text = deno_core::serde_json::to_string_pretty(value)?;
+  text.push('\n');
+  create_file(dir, filename, &text)
+}
+
 fn create_file(
   dir: &Path,
   filename: &str,
@@ -30,46 +165,3 @@ fn create_file(
     Ok(())
   }
 }
-
-pub fn init_project(init_flags: InitFlags) -> Result<(), AnyError> {
-  let cwd =
-    std::env::current_dir().context("Can't read current working directory.")?;
-  let dir = if let Some(dir) = &init_flags.dir {
-    let dir = cwd.join(dir);
-    std::fs::create_dir_all(&dir)?;
-    dir
-  } else {
-    cwd
-  };
-
-  let main_ts = include_str!("./templates/main.ts");
-  create_file(&dir, "main.ts", main_ts)?;
-
-  create_file(
-    &dir,
-    "main_test.ts",
-    include_str!("./templates/main_test.ts"),
-  )?;
-  create_file(&dir, "deno.json", include_str!("./templates/deno.json"))?;
-
-  info!("✅ {}", colors::green("Project initialized"));
-  info!("");
-  info!("{}", colors::gray("Run these commands to get started"));
-  info!("");
-  if let Some(dir) = init_flags.dir {
-    info!("  cd {}", dir);
-    info!("");
-  }
-  info!("  {}", colors::gray("# Run the program"));
-  info!("  deno run main.ts");
-  info!("");
-  info!(
-    "  {}",
-    colors::gray("# Run the program and watch for file changes")
-  );
-  info!("  deno task dev");
-  info!("");
-  info!("  {}", colors::gray("# Run the tests"));
-  info!("  deno test");
-  Ok(())
-}

cli/tools/init/templates/deno.json

@@ -1,5 +0,0 @@
-{
-  "tasks": {
-    "dev": "deno run --watch main.ts"
-  }
-}

cli/tools/init/templates/main.ts

@@ -1,8 +0,0 @@
-export function add(a: number, b: number): number {
-  return a + b;
-}
-
-// Learn more at https://deno.land/manual/examples/module_metadata#concepts
-if (import.meta.main) {
-  console.log("Add 2 + 3 =", add(2, 3));
-}

cli/tools/init/templates/main_test.ts

@@ -1,6 +0,0 @@
-import { assertEquals } from "jsr:@std/assert";
-import { add } from "./main.ts";
-
-Deno.test(function addTest() {
-  assertEquals(add(2, 3), 5);
-});

tests/specs/init/lib/__test__.jsonc

@@ -0,0 +1,16 @@
+{
+  "tempDir": true,
+  "steps": [{
+    "args": "init --lib project",
+    "output": "init.out"
+  }, {
+    "cwd": "project",
+    "args": "test",
+    "output": "test.out"
+  }, {
+    "cwd": "project",
+    "args": "publish --dry-run",
+    "output": "dry_publish.out",
+    "exitCode": 1
+  }]
+}

tests/specs/init/lib/dry_publish.out

@@ -0,0 +1,7 @@
+Check file:///[WILDLINE]/mod.ts
+Checking for slow types in the public API...
+Check file:///[WILDLINE]/mod.ts
+error: Failed preparing 'project'.
+
+Caused by:
+    Invalid package name, use '@<scope_name>/<package_name> format

tests/specs/init/lib/init.out

@@ -0,0 +1,14 @@
+✅ Project initialized
+
+Run these commands to get started
+
+  cd project
+
+  # Run the tests
+  deno test
+
+  # Run the tests and watch for file changes
+  deno task dev
+
+  # Publish to JSR (dry run)
+  deno publish --dry-run

tests/specs/init/lib/test.out

@@ -0,0 +1,14 @@
+Download http://127.0.0.1:4250/@std/assert/meta.json
+Download http://127.0.0.1:4250/@std/assert/0.220.1_meta.json
+[UNORDERED_START]
+Download http://127.0.0.1:4250/@std/assert/0.220.1/mod.ts
+Download http://127.0.0.1:4250/@std/assert/0.220.1/assert_equals.ts
+Download http://127.0.0.1:4250/@std/assert/0.220.1/assert.ts
+Download http://127.0.0.1:4250/@std/assert/0.220.1/fail.ts
+[UNORDERED_END]
+Check file:///[WILDLINE]/mod_test.ts
+running 1 test from ./mod_test.ts
+addTest ... ok ([WILDLINE])
+
+ok | 1 passed | 0 failed ([WILDLINE])
+