replace: add --literal option

to be consistent with the `--literal` option in `search` & `searchset`

src/cmd/replace.rs

@@ -24,6 +24,9 @@ replace arguments:
 replace options:
     -i, --ignore-case      Case insensitive search. This is equivalent to
                            prefixing the regex with '(?i)'.
+    --literal              Treat the regex pattern as a literal string. This allows
+                           you to search for exact matches that even contain special
+                           regex characters without escaping them.
     -s, --select <arg>     Select the columns to search. See 'qsv select -h'
                            for the full syntax.
     -u, --unicode          Enable unicode support. When enabled, character classes
@@ -50,7 +53,7 @@ Common options:
 
 "#;
 
-use std::{borrow::Cow, collections::HashSet, env};
+use std::{borrow::Cow, collections::HashSet};
 
 #[cfg(any(feature = "feature_capable", feature = "lite"))]
 use indicatif::{HumanCount, ProgressBar, ProgressDrawTarget};
@@ -75,6 +78,7 @@ struct Args {
     flag_no_headers:     bool,
     flag_delimiter:      Option<Delimiter>,
     flag_ignore_case:    bool,
+    flag_literal:        bool,
     flag_size_limit:     usize,
     flag_dfa_size_limit: usize,
     flag_progressbar:    bool,
@@ -85,11 +89,20 @@ const NULL_VALUE: &str = "<null>";
 
 pub fn run(argv: &[&str]) -> CliResult<()> {
     let args: Args = util::get_args(USAGE, argv)?;
-    let regex_unicode = match env::var("QSV_REGEX_UNICODE") {
-        Ok(_) => true,
-        Err(_) => args.flag_unicode,
+
+    let regex_unicode = if util::get_envvar_flag("QSV_REGEX_UNICODE") {
+        true
+    } else {
+        args.flag_unicode
+    };
+
+    let arg_pattern = if args.flag_literal {
+        regex::escape(&args.arg_pattern)
+    } else {
+        args.arg_pattern.clone()
     };
-    let pattern = RegexBuilder::new(&args.arg_pattern)
+
+    let pattern = RegexBuilder::new(&arg_pattern)
         .case_insensitive(args.flag_ignore_case)
         .unicode(regex_unicode)
         .size_limit(args.flag_size_limit * (1 << 20))

tests/test_replace.rs

@@ -28,6 +28,34 @@ fn replace() {
     wrk.assert_success(&mut cmd);
 }
 
+#[test]
+fn replace_regex_literal() {
+    let wrk = Workdir::new("replace");
+    wrk.create(
+        "data.csv",
+        vec![
+            svec!["identifier", "color"],
+            svec!["164.0", "yel$low^"],
+            svec!["165.0", "yellow"],
+            svec!["166.0", "yellow"],
+            svec!["167.0", "yel$low^.0"],
+        ],
+    );
+    let mut cmd = wrk.command("replace");
+    cmd.arg("$low^").arg("low").arg("--literal").arg("data.csv");
+
+    let got: Vec<Vec<String>> = wrk.read_stdout(&mut cmd);
+    let expected = vec![
+        svec!["identifier", "color"],
+        svec!["164.0", "yellow"],
+        svec!["165.0", "yellow"],
+        svec!["166.0", "yellow"],
+        svec!["167.0", "yellow.0"],
+    ];
+    assert_eq!(got, expected);
+    wrk.assert_success(&mut cmd);
+}
+
 #[test]
 fn replace_match() {
     let wrk = Workdir::new("replace_match");