From 52525a156ff2a9f5c8c6fbb2e933ec412afb4728 Mon Sep 17 00:00:00 2001
From: Maxime Coste <frrrwww@gmail.com>
Date: Mon, 7 Mar 2016 20:17:41 +0000
Subject: [PATCH] Remove complete_prefix option and behaviour

Now that we use subsequence based completion almost everywhere,
completing the common prefix does not make sense anymore.
---
 README.asciidoc               |  2 --
 doc/manpages/options.asciidoc |  4 ---
 src/input_handler.cc          | 47 +++++------------------------------
 src/main.cc                   |  3 ---
 4 files changed, 6 insertions(+), 50 deletions(-)

diff --git a/README.asciidoc b/README.asciidoc
index ff1abe27..14a2c8bf 100644
--- a/README.asciidoc
+++ b/README.asciidoc
@@ -813,8 +813,6 @@ Some options are built in Kakoune, and can be used to control it's behaviour:
    writing a buffer, this is autodetected on load.
  * `BOM` _enum(none|utf8)_: define if the file should be written
    with an unicode byte order mark.
- * `complete_prefix` _bool_: when completing in command line, and multiple
-   candidates exist, enable completion with common prefix.
  * `incsearch` _bool_: execute search as it is typed
  * `aligntab` _bool_: use tabs for alignment command
  * `autoinfo` _flags(command|onkey|normal)_: display automatic information
diff --git a/doc/manpages/options.asciidoc b/doc/manpages/options.asciidoc
index 53fd6802..7edd4f8e 100644
--- a/doc/manpages/options.asciidoc
+++ b/doc/manpages/options.asciidoc
@@ -66,10 +66,6 @@ Builtin options
 *BOM* 'enum(none|utf8)'::
 	define if the file should be written with an unicode byte order mark
 
-*complete_prefix* 'bool'::
-	when completing in command line, and multiple candidates exist,
-	enable completion with common prefix
-
 *incsearch* 'bool'::
 	execute search as it is typed
 
diff --git a/src/input_handler.cc b/src/input_handler.cc
index 1f307f67..3871398d 100644
--- a/src/input_handler.cc
+++ b/src/input_handler.cc
@@ -762,51 +762,16 @@ public:
             const bool reverse = (key == Key::BackTab);
             CandidateList& candidates = m_completions.candidates;
             // first try, we need to ask our completer for completions
-            bool updated_completions = false;
             if (candidates.empty())
-            {
                 refresh_completions(CompletionFlags::None);
 
-                if (candidates.empty())
-                    return;
-                updated_completions = true;
-            }
-            bool did_prefix = false;
-            if (m_current_completion == -1 and
-                context().options()["complete_prefix"].get<bool>())
-            {
-                const String& line = m_line_editor.line();
-                CandidateList& candidates = m_completions.candidates;
-                String prefix = common_prefix(candidates);
-                if (m_completions.end - m_completions.start > prefix.length())
-                    prefix = line.substr(m_completions.start,
-                                         m_completions.end - m_completions.start).str();
+            if (candidates.empty())
+                return;
 
-                if (not prefix.empty())
-                {
-                    auto it = find(candidates, prefix);
-                    if (it == candidates.end())
-                    {
-                        m_current_completion = candidates.size();
-                        candidates.push_back(prefix);
-                    }
-                    else
-                        m_current_completion = it - candidates.begin();
-
-                    CharCount start = line.char_count_to(m_completions.start);
-                    // When we just updated completions, select the common
-                    // prefix even if it was the currently entered text.
-                    did_prefix = updated_completions or
-                                 prefix != line.substr(start, m_line_editor.cursor_pos() - start);
-                }
-            }
-            if (not did_prefix)
-            {
-                if (not reverse and ++m_current_completion >= candidates.size())
-                    m_current_completion = 0;
-                else if (reverse and --m_current_completion < 0)
-                    m_current_completion = candidates.size()-1;
-            }
+            if (not reverse and ++m_current_completion >= candidates.size())
+                m_current_completion = 0;
+            else if (reverse and --m_current_completion < 0)
+                m_current_completion = candidates.size()-1;
 
             const String& completion = candidates[m_current_completion];
             if (context().has_client())
diff --git a/src/main.cc b/src/main.cc
index 960ba7ec..11f6c11d 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -206,9 +206,6 @@ void register_options()
     reg.declare_option("eolformat", "end of line format: crlf or lf", EolFormat::Lf);
     reg.declare_option("BOM", "insert a byte order mark when writing buffer (none or utf8)",
                        ByteOrderMark::None);
-    reg.declare_option("complete_prefix",
-                       "complete up to common prefix in tab completion",
-                       true);
     reg.declare_option("incsearch",
                        "incrementaly apply search/select/split regex",
                        true);