move numfmt help to a separate file

src/uu/numfmt/help.md

@@ -0,0 +1,42 @@
+<!-- spell-checker:ignore N'th M'th -->
+# numfmt
+
+## About
+
+Convert numbers from/to human-readable strings
+
+## Long Help
+
+UNIT options:
+   none   no auto-scaling is done; suffixes will trigger an error
+
+   auto   accept optional single/two letter suffix:
+
+          1K = 1000, 1Ki = 1024, 1M = 1000000, 1Mi = 1048576,
+
+   si     accept optional single letter suffix:
+
+          1K = 1000, 1M = 1000000, ...
+
+   iec    accept optional single letter suffix:
+
+          1K = 1024, 1M = 1048576, ...
+
+   iec-i  accept optional two-letter suffix:
+
+          1Ki = 1024, 1Mi = 1048576, ...
+
+FIELDS supports cut(1) style field ranges:
+  N    N'th field, counted from 1
+  N-   from N'th field, to end of line
+  N-M  from N'th to M'th field (inclusive)
+  -M   from first to M'th field (inclusive)
+  -    all fields
+Multiple fields/ranges can be separated with commas
+
+FORMAT must be suitable for printing one floating-point argument '%f'.
+Optional quote (%'f) will enable --grouping (if supported by current locale).
+Optional width value (%10f) will pad output. Optional zero (%010f) width
+will zero pad the number. Optional negative values (%-10f) will left align.
+Optional precision (%.1f) will override the input determined precision.
+

src/uu/numfmt/src/numfmt.rs

@@ -5,8 +5,6 @@
 //  * For the full copyright and license information, please view the LICENSE
 //  * file that was distributed with this source code.
 
-// spell-checker:ignore N'th M'th
-
 use crate::errors::*;
 use crate::format::format_and_print;
 use crate::options::*;
@@ -17,47 +15,15 @@ use units::{IEC_BASES, SI_BASES};
 use uucore::display::Quotable;
 use uucore::error::UResult;
 use uucore::ranges::Range;
-use uucore::{format_usage, InvalidEncodingHandling};
+use uucore::{format_usage, help_section, InvalidEncodingHandling};
 
 pub mod errors;
 pub mod format;
 pub mod options;
 mod units;
 
-static ABOUT: &str = "Convert numbers from/to human-readable strings";
-static LONG_HELP: &str = "UNIT options:
-   none   no auto-scaling is done; suffixes will trigger an error
-
-   auto   accept optional single/two letter suffix:
-
-          1K = 1000, 1Ki = 1024, 1M = 1000000, 1Mi = 1048576,
-
-   si     accept optional single letter suffix:
-
-          1K = 1000, 1M = 1000000, ...
-
-   iec    accept optional single letter suffix:
-
-          1K = 1024, 1M = 1048576, ...
-
-   iec-i  accept optional two-letter suffix:
-
-          1Ki = 1024, 1Mi = 1048576, ...
-
-FIELDS supports cut(1) style field ranges:
-  N    N'th field, counted from 1
-  N-   from N'th field, to end of line
-  N-M  from N'th to M'th field (inclusive)
-  -M   from first to M'th field (inclusive)
-  -    all fields
-Multiple fields/ranges can be separated with commas
-
-FORMAT must be suitable for printing one floating-point argument '%f'.
-Optional quote (%'f) will enable --grouping (if supported by current locale).
-Optional width value (%10f) will pad output. Optional zero (%010f) width
-will zero pad the number. Optional negative values (%-10f) will left align.
-Optional precision (%.1f) will override the input determined precision.
-";
+const ABOUT: &str = help_section!("about");
+const LONG_HELP: &str = help_section!("long help");
 const USAGE: &str = "{} [OPTION]... [NUMBER]...";
 
 fn handle_args<'a>(args: impl Iterator<Item = &'a str>, options: &NumfmtOptions) -> UResult<()> {

src/uucore_procs/src/lib.rs

@@ -1,7 +1,9 @@
 // Copyright (C) ~ Roy Ivy III <rivy.dev@gmail.com>; MIT license
 
 extern crate proc_macro;
-use proc_macro::TokenStream;
+use std::{fs::File, io::Read, path::PathBuf};
+
+use proc_macro::{Literal, TokenStream, TokenTree};
 use quote::quote;
 
 //## rust proc-macro background info
@@ -34,3 +36,40 @@ pub fn main(_args: TokenStream, stream: TokenStream) -> TokenStream {
 
     TokenStream::from(new)
 }
+
+#[proc_macro]
+pub fn help_section(input: TokenStream) -> TokenStream {
+    let input: Vec<TokenTree> = input.into_iter().collect();
+    let value = match &input.get(0) {
+        Some(TokenTree::Literal(literal)) => literal.to_string(),
+        _ => panic!("Input to help_section should be a string literal!"),
+    };
+    let input_str: String = value.parse().unwrap();
+    let input_str = input_str.to_lowercase().trim_matches('"').to_string();
+
+    let mut content = String::new();
+    let mut path = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
+
+    path.push("help.md");
+
+    File::open(path)
+        .unwrap()
+        .read_to_string(&mut content)
+        .unwrap();
+
+    let text = content
+        .lines()
+        .skip_while(|&l| {
+            l.strip_prefix("##")
+                .map_or(true, |l| l.trim().to_lowercase() != input_str)
+        })
+        .skip(1)
+        .take_while(|l| !l.starts_with("##"))
+        .collect::<Vec<_>>()
+        .join("\n")
+        .trim()
+        .to_string();
+
+    let str = TokenTree::Literal(Literal::string(&text));
+    str.into()
+}