Feat: Finished functionality

- Added test suite
- Added README.md

Cargo.lock

@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43f6cb1bf222025340178f382c426f13757b2960e89779dfcb319c32542a5a41"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "anstream"
 version = "0.3.2"
@@ -51,12 +60,44 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "assert_cmd"
+version = "2.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "88903cb14723e4d4003335bb7f8a14f27691649105346a0f0957466c096adfe6"
+dependencies = [
+ "anstyle",
+ "bstr",
+ "doc-comment",
+ "predicates",
+ "predicates-core",
+ "predicates-tree",
+ "wait-timeout",
+]
+
+[[package]]
+name = "autocfg"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
+
 [[package]]
 name = "bitflags"
 version = "2.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "630be753d4e58660abd17930c71b647fe46c27ea6b63cc59e1e3851406972e42"
 
+[[package]]
+name = "bstr"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6798148dccfbff0fae41c7574d2fa8f1ef3492fba0face179de5d8d447d67b05"
+dependencies = [
+ "memchr",
+ "regex-automata",
+ "serde",
+]
+
 [[package]]
 name = "cc"
 version = "1.0.79"
@@ -97,13 +138,33 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "acbf1af155f9b9ef647e42cdc158db4b64a1b61f743629225fde6f3e0be2a7c7"
 
+[[package]]
+name = "difflib"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6184e33543162437515c2e2b48714794e37845ec9851711914eec9d308f6ebe8"
+
+[[package]]
+name = "doc-comment"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
+
 [[package]]
 name = "echor"
 version = "0.1.0"
 dependencies = [
+ "assert_cmd",
  "clap",
+ "predicates",
 ]
 
+[[package]]
+name = "either"
+version = "1.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7fcaabb2fef8c910e7f4c7ce9f67a1283a1715879a7c230ca9d6d1ae31f16d91"
+
 [[package]]
 name = "errno"
 version = "0.3.1"
@@ -125,6 +186,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "float-cmp"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "98de4bbd547a563b716d8dfa9aad1cb19bfab00f4fa09a6a4ed21dbcf44ce9c4"
+dependencies = [
+ "num-traits",
+]
+
 [[package]]
 name = "hermit-abi"
 version = "0.3.2"
@@ -142,6 +212,15 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "itertools"
+version = "0.10.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b0fd2260e829bddf4cb6ea802289de2f86d6a7a690192fbe91b3f46e0f2c8473"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.147"
@@ -154,12 +233,93 @@ version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "09fc20d2ca12cb9f044c93e3bd6d32d523e6e2ec3db4f7b2939cd99026ecd3f0"
 
+[[package]]
+name = "memchr"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+
+[[package]]
+name = "normalize-line-endings"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "61807f77802ff30975e01f4f071c8ba10c022052f98b3294119f3e615d13e5be"
+
+[[package]]
+name = "num-traits"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "578ede34cf02f8924ab9447f50c28075b4d3e5b269972345e7e0372b38c6cdcd"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "once_cell"
 version = "1.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dd8b5dd2ae5ed71462c540258bedcb51965123ad7e7ccf4b9a8cafaa4a63576d"
 
+[[package]]
+name = "predicates"
+version = "3.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09963355b9f467184c04017ced4a2ba2d75cbcb4e7462690d388233253d4b1a9"
+dependencies = [
+ "anstyle",
+ "difflib",
+ "float-cmp",
+ "itertools",
+ "normalize-line-endings",
+ "predicates-core",
+ "regex",
+]
+
+[[package]]
+name = "predicates-core"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b794032607612e7abeb4db69adb4e33590fa6cf1149e95fd7cb00e634b92f174"
+
+[[package]]
+name = "predicates-tree"
+version = "1.0.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "368ba315fb8c5052ab692e68a0eefec6ec57b23a36959c14496f0b0df2c0cecf"
+dependencies = [
+ "predicates-core",
+ "termtree",
+]
+
+[[package]]
+name = "regex"
+version = "1.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2eae68fc220f7cf2532e4494aded17545fce192d59cd996e0fe7887f4ceb575"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "39354c10dd07468c2e73926b23bb9c2caca74c5501e38a35da70406f1d923310"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e5ea92a5b6195c6ef2a0295ea818b312502c6fc94dde986c5553242e18fd4ce2"
+
 [[package]]
 name = "rustix"
 version = "0.38.4"
@@ -173,18 +333,39 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "serde"
+version = "1.0.173"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e91f70896d6720bc714a4a57d22fc91f1db634680e65c8efe13323f1fa38d53f"
+
 [[package]]
 name = "strsim"
 version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "73473c0e59e6d5812c5dfe2a064a6444949f089e20eec9a2e5506596494e4623"
 
+[[package]]
+name = "termtree"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3369f5ac52d5eb6ab48c6b4ffdc8efbcad6b89c765749064ba298f2c68a16a76"
+
 [[package]]
 name = "utf8parse"
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "711b9620af191e0cdc7468a8d14e709c3dcdb115b36f838e601583af800a370a"
 
+[[package]]
+name = "wait-timeout"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9f200f5b12eb75f8c1ed65abd4b2db8a6e1b138a20de009dacee265a2498f3f6"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.48.0"

Cargo.toml

@@ -9,3 +9,7 @@ description = "Rust rewrite of echo"
 
 [dependencies]
 clap = { version = "4", features = ["cargo", "help"] }
+
+[dev-dependencies]
+assert_cmd = "2.0.12"
+predicates = "3.0.3"

README.md

@@ -0,0 +1,8 @@
+# Echor - A Rust Rewrite of GNU/BSD echo program
+
+## Build
+
+`cargo build`
+
+## Test
+`cargo test`

src/main.rs

@@ -1,8 +1,8 @@
 use clap::builder::{Arg, Command};
-use clap::{crate_authors, crate_description, crate_name, crate_version};
+use clap::{crate_authors, crate_description, crate_name, crate_version, ArgAction, ArgMatches};
 
 fn main() {
-    let matches = Command::new(crate_name!())
+    let matches: ArgMatches = Command::new(crate_name!())
         .version(crate_version!())
         .author(crate_authors!("\n"))
         .about(crate_description!())
@@ -15,7 +15,7 @@ fn main() {
 ",
         )
         .arg(
-            Arg::new("test")
+            Arg::new("text")
                 .value_name("TEXT")
                 .help("Input text")
                 .required(true)
@@ -25,9 +25,25 @@ fn main() {
             Arg::new("omit_newline")
                 .short('n')
                 .help("Do not print newline")
-                .num_args(0),
+                .num_args(0)
+                .action(ArgAction::SetTrue),
         )
         .get_matches();
 
-    println!("{:#?}", matches);
+    let text: Vec<&str> = matches
+        .get_many::<String>("text")
+        .expect("Must contains text argument")
+        .map(|s| s.as_str())
+        .collect();
+
+    // If the -n flag is passed, we do not print new line
+    print!(
+        "{}{}",
+        text.join(" "),
+        if matches.get_flag("omit_newline") {
+            ""
+        } else {
+            "\n"
+        }
+    );
 }

tests/cli.rs

@@ -0,0 +1,18 @@
+use assert_cmd::Command;
+use predicates::prelude::*;
+
+#[test]
+fn dies_no_args() {
+    let mut cmd = Command::cargo_bin("echor").expect("cargo binary error");
+
+    cmd.assert()
+        .failure()
+        .stderr(predicate::str::contains("Usage"));
+}
+
+#[test]
+fn runs() {
+    let mut cmd = Command::cargo_bin("echor").expect("cargo binary error");
+
+    cmd.arg("hello").assert().success();
+}