From 4a003782a51a94259ef3b5ddfacb2a148c5056e7 Mon Sep 17 00:00:00 2001
From: kraem <ebrin.ronnie@protonmail.com>
Date: Mon, 20 Sep 2021 06:45:07 +0200
Subject: [PATCH] enable smart case regex search by default (#761)

---
 TODO.md                    |  2 --
 book/src/configuration.md  |  1 +
 book/src/keymap.md         |  3 +--
 helix-term/src/commands.rs | 12 ++++++++++--
 helix-term/src/ui/mod.rs   | 12 +++++++++++-
 helix-view/src/editor.rs   |  3 +++
 6 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/TODO.md b/TODO.md
index d81cf302..90e7e450 100644
--- a/TODO.md
+++ b/TODO.md
@@ -22,8 +22,6 @@ as you type completion!
 
 - [ ] lsp: signature help
 
-- [ ] search: smart case by default: insensitive unless upper detected
-
 2
 - [ ] macro recording
 - [ ] extend selection (treesitter select parent node) (replaces viw, vi(, va( etc )
diff --git a/book/src/configuration.md b/book/src/configuration.md
index 5a28362d..90cdd8a7 100644
--- a/book/src/configuration.md
+++ b/book/src/configuration.md
@@ -17,6 +17,7 @@ To override global configuration parameters, create a `config.toml` file located
 | `scroll-lines` | Number of lines to scroll per scroll wheel step. | `3` |
 | `shell` | Shell to use when running external commands. | Unix: `["sh", "-c"]`<br/>Windows: `["cmd", "/C"]` |
 | `line-number` | Line number display (`absolute`, `relative`) | `absolute` |
+| `smart-case` | Enable smart case regex searching (case insensitive unless pattern contains upper case characters) | `true` |
 
 ## LSP
 
diff --git a/book/src/keymap.md b/book/src/keymap.md
index 4fa5033d..16d2420d 100644
--- a/book/src/keymap.md
+++ b/book/src/keymap.md
@@ -104,8 +104,7 @@
 
 ### Search
 
-> TODO: The search implementation isn't ideal yet -- we don't support searching
-in reverse, or searching via smartcase.
+> TODO: The search implementation isn't ideal yet -- we don't support searching in reverse.
 
 | Key   | Description                                 | Command              |
 | ----- | -----------                                 | -------              |
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index 703b92d1..d40bb9cf 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -5,7 +5,7 @@ use helix_core::{
     match_brackets,
     movement::{self, Direction},
     object, pos_at_coords,
-    regex::{self, Regex},
+    regex::{self, Regex, RegexBuilder},
     register::Register,
     search, selection, surround, textobject, LineEnding, Position, Range, Rope, RopeGraphemes,
     RopeSlice, Selection, SmallVec, Tendril, Transaction,
@@ -1154,7 +1154,15 @@ fn search_next_impl(cx: &mut Context, extend: bool) {
     if let Some(query) = registers.read('/') {
         let query = query.last().unwrap();
         let contents = doc.text().slice(..).to_string();
-        if let Ok(regex) = Regex::new(query) {
+        let case_insensitive = if cx.editor.config.smart_case {
+            !query.chars().any(char::is_uppercase)
+        } else {
+            false
+        };
+        if let Ok(regex) = RegexBuilder::new(query)
+            .case_insensitive(case_insensitive)
+            .build()
+        {
             search_impl(doc, view, &contents, &regex, extend);
         } else {
             // get around warning `mutable_borrow_reservation_conflict`
diff --git a/helix-term/src/ui/mod.rs b/helix-term/src/ui/mod.rs
index 07eef352..f6536eb2 100644
--- a/helix-term/src/ui/mod.rs
+++ b/helix-term/src/ui/mod.rs
@@ -20,6 +20,7 @@ pub use spinner::{ProgressSpinners, Spinner};
 pub use text::Text;
 
 use helix_core::regex::Regex;
+use helix_core::regex::RegexBuilder;
 use helix_view::{Document, Editor, View};
 
 use std::path::PathBuf;
@@ -53,7 +54,16 @@ pub fn regex_prompt(
                         return;
                     }
 
-                    match Regex::new(input) {
+                    let case_insensitive = if cx.editor.config.smart_case {
+                        !input.chars().any(char::is_uppercase)
+                    } else {
+                        false
+                    };
+
+                    match RegexBuilder::new(input)
+                        .case_insensitive(case_insensitive)
+                        .build()
+                    {
                         Ok(regex) => {
                             let (view, doc) = current!(cx.editor);
 
diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
index a3d0d032..b7df4a9b 100644
--- a/helix-view/src/editor.rs
+++ b/helix-view/src/editor.rs
@@ -39,6 +39,8 @@ pub struct Config {
     pub line_number: LineNumber,
     /// Middle click paste support. Defaults to true
     pub middle_click_paste: bool,
+    /// Smart case: Case insensitive searching unless pattern contains upper case characters. Defaults to true.
+    pub smart_case: bool,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Deserialize)]
@@ -64,6 +66,7 @@ impl Default for Config {
             },
             line_number: LineNumber::Absolute,
             middle_click_paste: true,
+            smart_case: true,
         }
     }
 }