Add `--max-filesize` option to cli

The --max-filesize option allows filtering files which are larger than
the specified limit. This is potentially useful if one is attempting to
search a number of large files without common file-types/suffixes.

See #369.

7 files changed, 96 insertions, 3 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 2a079292..bac7e3f4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -45,6 +45,7 @@ termcolor = { version = "0.3.0", path = "termcolor" }
 [build-dependencies]
 clap = "2.18"
 lazy_static = "0.2"
+regex = "0.2.1"
 
 [features]
 avx-accel = ["bytecount/avx-accel"]
diff --git a/build.rs b/build.rs
index 8a7c4900..4d0e2d13 100644
--- a/build.rs
+++ b/build.rs
@@ -2,6 +2,7 @@
 extern crate clap;
 #[macro_use]
 extern crate lazy_static;
+extern crate regex;
 
 use std::env;
 use std::fs;
diff --git a/doc/rg.1 b/doc/rg.1
index cbc0c89e..1b66f2a2 100644
--- a/doc/rg.1
+++ b/doc/rg.1
@@ -1,4 +1,4 @@
-.\" Automatically generated by Pandoc 1.19.1
+.\" Automatically generated by Pandoc 1.19.2.1
 .\"
 .TH "rg" "1"
 .hy
@@ -275,11 +275,21 @@ Follow symlinks.
 .RS
 .RE
 .TP
-.B \-m, \-\-max\-count NUM
+.B \-m, \-\-max\-count \f[I]NUM\f[]
 Limit the number of matching lines per file searched to NUM.
 .RS
 .RE
 .TP
+.B \-\-max\-filesize \f[I]NUM\f[]+\f[I]SUFFIX\f[]?
+Ignore files larger than \f[I]NUM\f[] in size.
+Directories will never be ignored.
+.RS
+.PP
+\f[I]SUFFIX\f[] is optional and may be one of K, M or G.
+These correspond to kilobytes, megabytes and gigabytes respectively.
+If omitted the input is treated as bytes.
+.RE
+.TP
 .B \-\-maxdepth \f[I]NUM\f[]
 Descend at most NUM directories below the command line arguments.
 A value of zero searches only the starting\-points themselves.
diff --git a/doc/rg.1.md b/doc/rg.1.md
index 8804fcc5..830a3bb4 100644
--- a/doc/rg.1.md
+++ b/doc/rg.1.md
@@ -187,9 +187,16 @@ Project home page: https://github.com/BurntSushi/ripgrep
 -L, --follow
 : Follow symlinks.
 
--m, --max-count NUM
+-m, --max-count *NUM*
 : Limit the number of matching lines per file searched to NUM.
 
+--max-filesize *NUM*+*SUFFIX*?
+: Ignore files larger than *NUM* in size. Directories will never be ignored.
+
+    *SUFFIX* is optional and may be one of K, M or G. These correspond to
+    kilobytes, megabytes and gigabytes respectively. If omitted the input is
+    treated as bytes.
+
 --maxdepth *NUM*
 : Descend at most NUM directories below the command line arguments.
   A value of zero searches only the starting-points themselves.
diff --git a/src/app.rs b/src/app.rs
index 9ead9c5b..6d5177c4 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 
 use clap::{App, AppSettings, Arg, ArgSettings};
+use regex::Regex;
 
 const ABOUT: &'static str = "
 ripgrep (rg) recursively searches your current directory for a regex pattern.
@@ -145,6 +146,9 @@ fn app<F>(next_line_help: bool, doc: F) -> App<'static, 'static>
         .arg(flag("max-count")
              .short("m").value_name("NUM").takes_value(true)
              .validator(validate_number))
+        .arg(flag("max-filesize")
+             .value_name("NUM+SUFFIX?").takes_value(true)
+             .validator(validate_max_filesize))
         .arg(flag("maxdepth")
              .value_name("NUM").takes_value(true)
              .validator(validate_number))
@@ -371,6 +375,13 @@ lazy_static! {
         doc!(h, "max-count",
              "Limit the number of matches.",
              "Limit the number of matching lines per file searched to NUM.");
+        doc!(h, "max-filesize",
+             "Ignore files larger than NUM in size.",
+             "Ignore files larger than NUM in size. Does not ignore directories. \
+              \n\nThe input format accepts suffixes of K, M or G which \
+              correspond to kilobytes, megabytes and gigabytes. If no suffix is \
+              provided the input is treated as bytes. \
+              \n\nExample: --max-filesize 50K or --max-filesize 80M");
         doc!(h, "maxdepth",
              "Descend at most NUM directories.",
              "Limit the depth of directory traversal to NUM levels beyond \
@@ -491,3 +502,24 @@ lazy_static! {
 fn validate_number(s: String) -> Result<(), String> {
     s.parse::<usize>().map(|_|()).map_err(|err| err.to_string())
 }
+
+fn validate_max_filesize(s: String) -> Result<(), String> {
+    let re = Regex::new(r#"^(\d+)([KMG])?$"#).unwrap();
+    let caps = try!(re.captures(&s)
+                      .ok_or("invalid format for max-filesize argument"));
+
+    let value = caps.get(1);
+    let suffix = caps.get(2).map(|x| x.as_str());
+
+    match value {
+        Some(value) => {
+            try!(value.as_str().parse::<u64>().map_err(|err| err.to_string()));
+        }
+        None => ()
+    }
+
+    match suffix {
+        None | Some("K") | Some("M") | Some("G") => Ok(()),
+        _ => Err(From::from("invalid suffix for max-filesize argument"))
+    }
+}
diff --git a/src/args.rs b/src/args.rs
index a968617f..5f6d9916 100644
--- a/src/args.rs
+++ b/src/args.rs
@@ -55,6 +55,7 @@ pub struct Args {
     line_number: bool,
     line_per_match: bool,
     max_count: Option<u64>,
+    max_filesize: Option<u64>,
     maxdepth: Option<usize>,
     mmap: bool,
     no_ignore: bool,
@@ -285,6 +286,7 @@ impl Args {
         wd.follow_links(self.follow);
         wd.hidden(!self.hidden);
         wd.max_depth(self.maxdepth);
+        wd.max_filesize(self.max_filesize);
         wd.overrides(self.glob_overrides.clone());
         wd.types(self.types.clone());
         wd.git_global(!self.no_ignore && !self.no_ignore_vcs);
@@ -342,6 +344,7 @@ impl<'a> ArgMatches<'a> {
             line_number: self.line_number(),
             line_per_match: self.is_present("vimgrep"),
             max_count: try!(self.usize_of("max-count")).map(|max| max as u64),
+            max_filesize: try!(self.max_filesize()),
             maxdepth: try!(self.usize_of("maxdepth")),
             mmap: mmap,
             no_ignore: self.no_ignore(),
@@ -779,6 +782,33 @@ impl<'a> ArgMatches<'a> {
         btypes.build().map_err(From::from)
     }
 
+    /// Parses the max-filesize argument option into a byte count.
+    fn max_filesize(&self) -> Result<Option<u64>> {
+        use regex::Regex;
+
+        let max_filesize = match self.value_of_lossy("max-filesize") {
+            Some(x) => x,
+            None => return Ok(None)
+        };
+
+        let re = Regex::new(r#"^(\d+)([KMG])?$"#).unwrap();
+        let caps = try!(re.captures(&max_filesize)
+                          .ok_or("invalid format for max-filesize argument"));
+
+        let value = match caps.get(1) {
+            Some(value) => Some(try!(value.as_str().parse::<u64>())),
+            None => None
+        };
+        let suffix = caps.get(2).map(|x| x.as_str());
+        match suffix {
+            None      => Ok(value),
+            Some("K") => Ok(value.map(|x| x * 1024)),
+            Some("M") => Ok(value.map(|x| x * 1024 * 1024)),
+            Some("G") => Ok(value.map(|x| x * 1024 * 1024 * 1024)),
+            _ => Err(From::from("invalid suffix for max-filesize argument"))
+        }
+    }
+
     /// Returns true if ignore files should be ignored.
     fn no_ignore(&self) -> bool {
         self.is_present("no-ignore")
diff --git a/tests/tests.rs b/tests/tests.rs
index aeacca54..fd60d672 100644
--- a/tests/tests.rs
+++ b/tests/tests.rs
@@ -432,6 +432,18 @@ sherlock!(context_line_numbers, "world|attached",
     assert_eq!(lines, expected);
 });
 
+sherlock!(max_filesize_parse_error_length, "Sherlock", ".",
+|wd: WorkDir, mut cmd: Command| {
+    cmd.arg("--max-filesize").arg("44444444444444444444");
+    wd.assert_err(&mut cmd);
+});
+
+sherlock!(max_filesize_parse_error_suffix, "Sherlock", ".",
+|wd: WorkDir, mut cmd: Command| {
+    cmd.arg("--max-filesize").arg("45k");
+    wd.assert_err(&mut cmd);
+});
+
 sherlock!(ignore_hidden, "Sherlock", ".", |wd: WorkDir, mut cmd: Command| {
     wd.remove("sherlock");
     wd.create(".sherlock", hay::SHERLOCK);