diff options
Diffstat (limited to 'src/doc/book/listings/ch13-functional-features/listing-13-20')
5 files changed, 150 insertions, 0 deletions
diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-20/Cargo.lock b/src/doc/book/listings/ch13-functional-features/listing-13-20/Cargo.lock new file mode 100644 index 000000000..88bf82d16 --- /dev/null +++ b/src/doc/book/listings/ch13-functional-features/listing-13-20/Cargo.lock @@ -0,0 +1,6 @@ +# This file is automatically @generated by Cargo. +# It is not intended for manual editing. +[[package]] +name = "minigrep" +version = "0.1.0" + diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-20/Cargo.toml b/src/doc/book/listings/ch13-functional-features/listing-13-20/Cargo.toml new file mode 100644 index 000000000..64c2a3f52 --- /dev/null +++ b/src/doc/book/listings/ch13-functional-features/listing-13-20/Cargo.toml @@ -0,0 +1,6 @@ +[package] +name = "minigrep" +version = "0.1.0" +edition = "2021" + +[dependencies] diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-20/poem.txt b/src/doc/book/listings/ch13-functional-features/listing-13-20/poem.txt new file mode 100644 index 000000000..870752731 --- /dev/null +++ b/src/doc/book/listings/ch13-functional-features/listing-13-20/poem.txt @@ -0,0 +1,9 @@ +I'm nobody! Who are you? +Are you nobody, too? +Then there's a pair of us - don't tell! +They'd banish us, you know. + +How dreary to be somebody! +How public, like a frog +To tell your name the livelong day +To an admiring bog! diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-20/src/lib.rs b/src/doc/book/listings/ch13-functional-features/listing-13-20/src/lib.rs new file mode 100644 index 000000000..4410964a7 --- /dev/null +++ b/src/doc/book/listings/ch13-functional-features/listing-13-20/src/lib.rs @@ -0,0 +1,113 @@ +use std::env; +use std::error::Error; +use std::fs; + +pub struct Config { + pub query: String, + pub file_path: String, + pub ignore_case: bool, +} + +// ANCHOR: here +impl Config { + pub fn build( + mut args: impl Iterator<Item = String>, + ) -> Result<Config, &'static str> { + args.next(); + + let query = match args.next() { + Some(arg) => arg, + None => return Err("Didn't get a query string"), + }; + + let file_path = match args.next() { + Some(arg) => arg, + None => return Err("Didn't get a file path"), + }; + + let ignore_case = env::var("IGNORE_CASE").is_ok(); + + Ok(Config { + query, + file_path, + ignore_case, + }) + } +} +// ANCHOR_END: here + +pub fn run(config: Config) -> Result<(), Box<dyn Error>> { + let contents = fs::read_to_string(config.file_path)?; + + let results = if config.ignore_case { + search_case_insensitive(&config.query, &contents) + } else { + search(&config.query, &contents) + }; + + for line in results { + println!("{line}"); + } + + Ok(()) +} + +pub fn search<'a>(query: &str, contents: &'a str) -> Vec<&'a str> { + let mut results = Vec::new(); + + for line in contents.lines() { + if line.contains(query) { + results.push(line); + } + } + + results +} + +pub fn search_case_insensitive<'a>( + query: &str, + contents: &'a str, +) -> Vec<&'a str> { + let query = query.to_lowercase(); + let mut results = Vec::new(); + + for line in contents.lines() { + if line.to_lowercase().contains(&query) { + results.push(line); + } + } + + results +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn case_sensitive() { + let query = "duct"; + let contents = "\ +Rust: +safe, fast, productive. +Pick three. +Duct tape."; + + assert_eq!(vec!["safe, fast, productive."], search(query, contents)); + } + + #[test] + fn case_insensitive() { + let query = "rUsT"; + let contents = "\ +Rust: +safe, fast, productive. +Pick three. +Trust me."; + + assert_eq!( + vec!["Rust:", "Trust me."], + search_case_insensitive(query, contents) + ); + } +} diff --git a/src/doc/book/listings/ch13-functional-features/listing-13-20/src/main.rs b/src/doc/book/listings/ch13-functional-features/listing-13-20/src/main.rs new file mode 100644 index 000000000..9ac022545 --- /dev/null +++ b/src/doc/book/listings/ch13-functional-features/listing-13-20/src/main.rs @@ -0,0 +1,16 @@ +use std::env; +use std::process; + +use minigrep::Config; + +fn main() { + let config = Config::build(env::args()).unwrap_or_else(|err| { + eprintln!("Problem parsing arguments: {err}"); + process::exit(1); + }); + + if let Err(e) = minigrep::run(config) { + eprintln!("Application error: {e}"); + process::exit(1); + } +} |