Implement uniq (#57)

Cargo.toml

@@ -12,8 +12,9 @@ members = [
     "pwd",
     "sleep",
     "true",
+    "tty",
     "whoami",
     "uname",
-    "tty",
+    "uniq",
     "yes"
 ]

uniq/.gitignore

@@ -0,0 +1,2 @@
+# For rls generated files in this directory
+/target

uniq/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "uniq"
+version = "0.0.1"
+authors = ["Vaibhav Yenamandra <yvvaibhav@gmail.com>"]
+build = "build.rs"
+edition = "2018"
+
+[dependencies]
+clap = { version = "^2.33.0", features = ["yaml", "wrap_help"] }
+coreutils_core = { path = "../coreutils_core" }
+
+[build-dependencies]
+clap = { version = "^2.33.0", features = ["yaml"] }

uniq/build.rs

@@ -0,0 +1,19 @@
+use std::env;
+
+use clap::{ App, Shell, load_yaml };
+
+fn main() {
+    let yaml = load_yaml!("src/uniq.yml");
+    let mut app = App::from_yaml(yaml);
+
+    let out_dir = match env::var("OUT_DIR") {
+        Ok(dir) => dir,
+        _ => return
+    };
+
+    app.gen_completions("uniq", Shell::Zsh, out_dir.clone());
+    app.gen_completions("uniq", Shell::Fish, out_dir.clone());
+    app.gen_completions("uniq", Shell::Bash, out_dir.clone());
+    app.gen_completions("uniq", Shell::PowerShell, out_dir.clone());
+    app.gen_completions("uniq", Shell::Elvish, out_dir);
+}

uniq/src/execution_options.rs

@@ -0,0 +1,88 @@
+use std::process;
+
+pub enum Counters {
+    All,
+    UniqueOnly,
+    DuplicateOnly
+}
+
+pub struct ExecutionOptions {
+    count_kind: Counters,
+    ignore_case: bool,
+    read_stdin: bool,
+    field_skip: u32,
+    char_skip: u32,
+    write_stdout: bool,
+    input_file_path: Option<String>,
+    output_file_path: Option<String>,
+}
+
+fn parse_num_or_panic(num_s: &str, message: String) -> u32 {
+    match num_s.parse() {
+        Ok(n) => n,
+        Err(_err) => {
+            eprintln!("{}", message);
+            process::exit(1);
+        }
+    }
+}
+
+/// Accept a match object from clap, and return a struct representing current
+/// CLI options
+///
+/// # Arguments
+/// * `matches` - A `clap::ArgMatches` object to transform into a struct
+///   representing the parameters of execution
+pub fn read_clap_matches(arg_matches: clap::ArgMatches) -> ExecutionOptions {
+    let read_stdin = !arg_matches.is_present("input_file");
+    let write_stdout = !arg_matches.is_present("output_file");
+
+    ExecutionOptions {
+        count_kind:
+            if arg_matches.is_present("duplicate-only") {
+                Counters::DuplicateOnly
+            } else if arg_matches.is_present("unique-only") {
+                Counters::UniqueOnly
+            } else {
+                Counters::All
+            },
+        ignore_case: arg_matches.is_present("ignore-case"),
+        field_skip: if arg_matches.is_present("num") {
+            let num_s = arg_matches.value_of("num").unwrap();
+            parse_num_or_panic(num_s,
+                               format!("uniq: Illegal field skip value: {}", num_s))
+        } else {
+            0
+        },
+        char_skip: if arg_matches.is_present("chars") {
+            let num_s = arg_matches.value_of("chars").unwrap();
+            parse_num_or_panic(num_s,
+                               format!("uniq: Illegal character skip value: {}", num_s))
+        } else {
+            0
+        },
+        read_stdin,
+        write_stdout,
+        input_file_path: if read_stdin {
+            None
+        } else {
+            match arg_matches.value_of("input_file") {
+                Some(ref path) =>
+                    if path == &"-" {
+                        None
+                    }  else {
+                        Some(path.to_string())
+                    }
+                None => None,
+            }
+        },
+        output_file_path: if write_stdout {
+            None
+        } else {
+            match arg_matches.value_of("output_file") {
+                Some(ref path) => Some(path.to_string()),
+                None => None,
+            }
+        },
+    }
+}

uniq/src/main.rs

@@ -0,0 +1,8 @@
+use clap::{load_yaml, App};
+
+mod execution_options;
+
+fn main() {
+    let yaml = load_yaml!("uniq.yml");
+    let _opts = execution_options::read_clap_matches(App::from_yaml(yaml).get_matches());
+}

uniq/src/uniq.yml

@@ -0,0 +1,34 @@
+name: uniq
+version: "0.0.0"
+author: Vaibhav Yenamandra <yvvaibhav+rust@gmail.com>
+about: "Report or fitler out duplicated lines from a file or stream.\nCommand descriptions taken from 'BSD General Commands Manual page for uniq.1'"
+args:
+    - count-all:
+        help: Precede each output line with the count of number of times the
+              line has occured, followed by a single space
+        short: c
+    - duplicate-only:
+        help: Only output lines that are repeated in the input
+        short: d
+    - unique-only:
+        help: Only output lines that are not repeated in the input
+        short: u
+    - ignore-case:
+        short: i
+        help: Turn on case insensitive comparison of lines
+    - num:
+        short: f
+        takes_value: true
+    - chars:
+        short: s
+        takes_value: true
+    - input_file:
+        takes_value: true
+    - output_file:
+        takes_value: true
+groups:
+    - counting-strategy:
+        args:
+            - count-all
+            - duplicate-only
+            - unique-only