feat: Add command-line option to list the supported licenses (#30)

* feat: added gplv2 and eupl (english)

* fix: added gpl2 to lib.rs

* feat: added list option to binary

* fix: formatting issue

* doc: added list argument to readme

Cargo.toml

@@ -7,7 +7,7 @@ license = "MIT"
 repository = "https://github.com/azu/license-generator"
 version = "1.2.0"
 authors = ["azu <[email protected]>"]
-edition = "2018"
+edition = "2021"
 include = [
     "files/**/*",
     "src/**/*",
@@ -16,5 +16,5 @@ include = [
     "LICENSE"
 ]
 [dependencies]
-structopt = "0.2.14"
+structopt = "0.3.26"
 chrono = "0.4"

README.md

@@ -27,6 +27,7 @@ Install with [Cargo](https://crates.io/):
     - Unlicense
 
     Options:
+      -l, --list lists the available licenses
       --author input author name. Default: `GitName <GitEmail>`
       --project input project name that is required by some license
       --year input license year

src/license.rs

@@ -2,6 +2,25 @@ pub trait License {
     fn notice(&self, year: u32, name: &str, project: &str) -> String;
 }
 
+pub const LICENSES: [&str; 16] = [
+    "AGPL",
+    "Apache",
+    "BSD",
+    "CC0",
+    "CC-BY",
+    "CC-BY-NC",
+    "CC-BY-NC-SA",
+    "CC-BY-SA",
+    "EUPL-1.2",
+    "GPL-2",
+    "GPL-3",
+    "ISC",
+    "LGPL-3",
+    "MIT",
+    "MPL-2",
+    "Unlicense"
+];
+
 // agpl-3.0.txt
 pub struct AGPL {}
 

src/main.rs

@@ -11,7 +11,9 @@ use std::process::{self, Command};
 
 #[derive(StructOpt, Debug)]
 struct Opt {
-    #[structopt(name = "INPUT", required = true)]
+    #[structopt(short, long, help = "Lists valid license types")]
+    list: bool,
+    #[structopt(name = "INPUT", required_unless("list"))]
     inputs: Vec<String>,
     #[structopt(long = "author")]
     author: Option<String>,
@@ -25,6 +27,17 @@ struct Opt {
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let opt = Opt::from_args();
+
+    if opt.list {
+        println!("Supported Licenses are:");
+        use license_generator::license::LICENSES;
+        for l in LICENSES {
+            print!("{}, ", l);
+        }
+        println!();
+        return Ok(());
+    } 
+
     let year = if let Some(year) = opt.year {
         year
     } else {