Merge remote-tracking branch 'upstream/master' into usermarksusermarks

1 files changed, 109 insertions, 38 deletions

diff --git a/src/nvim/lua/xdiff.c b/src/nvim/lua/xdiff.c
index b2b5dfedee..857b159af5 100644
--- a/src/nvim/lua/xdiff.c
+++ b/src/nvim/lua/xdiff.c
@@ -1,21 +1,26 @@
 // This is an open source non-commercial project. Dear PVS-Studio, please check
 // it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
 
-#include <errno.h>
 #include <lauxlib.h>
 #include <lua.h>
-#include <lualib.h>
-#include <stdio.h>
-#include <stdlib.h>
+#include <stdbool.h>
 #include <string.h>
 
+#include "luaconf.h"
+#include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
+#include "nvim/linematch.h"
 #include "nvim/lua/converter.h"
 #include "nvim/lua/executor.h"
 #include "nvim/lua/xdiff.h"
+#include "nvim/macros.h"
+#include "nvim/memory.h"
 #include "nvim/vim.h"
 #include "xdiff/xdiff.h"
 
+#define COMPARED_BUFFER0 (1 << 0)
+#define COMPARED_BUFFER1 (1 << 1)
+
 typedef enum {
   kNluaXdiffModeUnified = 0,
   kNluaXdiffModeOnHunkCB,
@@ -25,12 +30,81 @@ typedef enum {
 typedef struct {
   lua_State *lstate;
   Error *err;
+  mmfile_t *ma;
+  mmfile_t *mb;
+  bool linematch;
+  bool iwhite;
 } hunkpriv_t;
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "lua/xdiff.c.generated.h"
 #endif
 
+static void lua_pushhunk(lua_State *lstate, long start_a, long count_a, long start_b, long count_b)
+{
+  // Mimic extra offsets done by xdiff, see:
+  // src/xdiff/xemit.c:284
+  // src/xdiff/xutils.c:(356,368)
+  if (count_a > 0) {
+    start_a += 1;
+  }
+  if (count_b > 0) {
+    start_b += 1;
+  }
+  lua_createtable(lstate, 0, 0);
+  lua_pushinteger(lstate, start_a);
+  lua_rawseti(lstate, -2, 1);
+  lua_pushinteger(lstate, count_a);
+  lua_rawseti(lstate, -2, 2);
+  lua_pushinteger(lstate, start_b);
+  lua_rawseti(lstate, -2, 3);
+  lua_pushinteger(lstate, count_b);
+  lua_rawseti(lstate, -2, 4);
+  lua_rawseti(lstate, -2, (signed)lua_objlen(lstate, -2) + 1);
+}
+
+static void get_linematch_results(lua_State *lstate, mmfile_t *ma, mmfile_t *mb, long start_a,
+                                  long count_a, long start_b, long count_b, bool iwhite)
+{
+  // get the pointer to char of the start of the diff to pass it to linematch algorithm
+  const char *diff_begin[2] = { ma->ptr, mb->ptr };
+  int diff_length[2] = { (int)count_a, (int)count_b };
+
+  fastforward_buf_to_lnum(&diff_begin[0], start_a + 1);
+  fastforward_buf_to_lnum(&diff_begin[1], start_b + 1);
+
+  int *decisions = NULL;
+  size_t decisions_length = linematch_nbuffers(diff_begin, diff_length, 2, &decisions, iwhite);
+
+  long lnuma = start_a, lnumb = start_b;
+
+  long hunkstarta = lnuma;
+  long hunkstartb = lnumb;
+  long hunkcounta = 0;
+  long hunkcountb = 0;
+  for (size_t i = 0; i < decisions_length; i++) {
+    if (i && (decisions[i - 1] != decisions[i])) {
+      lua_pushhunk(lstate, hunkstarta, hunkcounta, hunkstartb, hunkcountb);
+
+      hunkstarta = lnuma;
+      hunkstartb = lnumb;
+      hunkcounta = 0;
+      hunkcountb = 0;
+      // create a new hunk
+    }
+    if (decisions[i] & COMPARED_BUFFER0) {
+      lnuma++;
+      hunkcounta++;
+    }
+    if (decisions[i] & COMPARED_BUFFER1) {
+      lnumb++;
+      hunkcountb++;
+    }
+  }
+  lua_pushhunk(lstate, hunkstarta, hunkcounta, hunkstartb, hunkcountb);
+  xfree(decisions);
+}
+
 static int write_string(void *priv, mmbuffer_t *mb, int nbuf)
 {
   luaL_Buffer *buf = (luaL_Buffer *)priv;
@@ -52,30 +126,15 @@ static int write_string(void *priv, mmbuffer_t *mb, int nbuf)
 // hunk_func callback used when opts.hunk_lines = true
 static int hunk_locations_cb(long start_a, long count_a, long start_b, long count_b, void *cb_data)
 {
-  // Mimic extra offsets done by xdiff, see:
-  // src/xdiff/xemit.c:284
-  // src/xdiff/xutils.c:(356,368)
-  if (count_a > 0) {
-    start_a += 1;
-  }
-  if (count_b > 0) {
-    start_b += 1;
+  hunkpriv_t *priv = (hunkpriv_t *)cb_data;
+  lua_State *lstate = priv->lstate;
+  if (priv->linematch) {
+    get_linematch_results(lstate, priv->ma, priv->mb, start_a, count_a, start_b, count_b,
+                          priv->iwhite);
+  } else {
+    lua_pushhunk(lstate, start_a, count_a, start_b, count_b);
   }
 
-  lua_State *lstate = (lua_State *)cb_data;
-  lua_createtable(lstate, 0, 0);
-
-  lua_pushinteger(lstate, start_a);
-  lua_rawseti(lstate, -2, 1);
-  lua_pushinteger(lstate, count_a);
-  lua_rawseti(lstate, -2, 2);
-  lua_pushinteger(lstate, start_b);
-  lua_rawseti(lstate, -2, 3);
-  lua_pushinteger(lstate, count_b);
-  lua_rawseti(lstate, -2, 4);
-
-  lua_rawseti(lstate, -2, (signed)lua_objlen(lstate, -2) + 1);
-
   return 0;
 }
 
@@ -149,7 +208,7 @@ static bool check_xdiff_opt(ObjectType actType, ObjectType expType, const char *
 }
 
 static NluaXdiffMode process_xdl_diff_opts(lua_State *lstate, xdemitconf_t *cfg, xpparam_t *params,
-                                           Error *err)
+                                           bool *linematch, Error *err)
 {
   const DictionaryOf(LuaRef) opts = nlua_pop_Dictionary(lstate, true, err);
 
@@ -205,6 +264,11 @@ static NluaXdiffMode process_xdl_diff_opts(lua_State *lstate, xdemitconf_t *cfg,
         goto exit_1;
       }
       cfg->interhunkctxlen = v->data.integer;
+    } else if (strequal("linematch", k.data)) {
+      *linematch = api_object_to_bool(*v, "linematch", false, err);
+      if (ERROR_SET(err)) {
+        goto exit_1;
+      }
     } else {
       struct {
         const char *name;
@@ -244,10 +308,8 @@ static NluaXdiffMode process_xdl_diff_opts(lua_State *lstate, xdemitconf_t *cfg,
 
   if (had_on_hunk) {
     mode = kNluaXdiffModeOnHunkCB;
-    cfg->hunk_func = call_on_hunk_cb;
   } else if (had_result_type_indices) {
     mode = kNluaXdiffModeLocations;
-    cfg->hunk_func = hunk_locations_cb;
   }
 
 exit_1:
@@ -268,6 +330,7 @@ int nlua_xdl_diff(lua_State *lstate)
   xdemitconf_t cfg;
   xpparam_t params;
   xdemitcb_t ecb;
+  bool linematch = false;
 
   CLEAR_FIELD(cfg);
   CLEAR_FIELD(params);
@@ -280,7 +343,7 @@ int nlua_xdl_diff(lua_State *lstate)
       return luaL_argerror(lstate, 3, "expected table");
     }
 
-    mode = process_xdl_diff_opts(lstate, &cfg, &params, &err);
+    mode = process_xdl_diff_opts(lstate, &cfg, &params, &linematch, &err);
 
     if (ERROR_SET(&err)) {
       goto exit_0;
@@ -288,7 +351,7 @@ int nlua_xdl_diff(lua_State *lstate)
   }
 
   luaL_Buffer buf;
-  hunkpriv_t *priv = NULL;
+  hunkpriv_t priv;
   switch (mode) {
   case kNluaXdiffModeUnified:
     luaL_buffinit(lstate, &buf);
@@ -296,14 +359,24 @@ int nlua_xdl_diff(lua_State *lstate)
     ecb.out_line = write_string;
     break;
   case kNluaXdiffModeOnHunkCB:
-    priv = xmalloc(sizeof(*priv));
-    priv->lstate = lstate;
-    priv->err = &err;
-    ecb.priv = priv;
+    cfg.hunk_func = call_on_hunk_cb;
+    priv = (hunkpriv_t) {
+      .lstate = lstate,
+      .err    = &err,
+    };
+    ecb.priv = &priv;
     break;
   case kNluaXdiffModeLocations:
+    cfg.hunk_func = hunk_locations_cb;
+    priv = (hunkpriv_t) {
+      .lstate    = lstate,
+      .ma        = &ma,
+      .mb        = &mb,
+      .linematch = linematch,
+      .iwhite    = (params.flags & XDF_IGNORE_WHITESPACE) > 0
+    };
+    ecb.priv = &priv;
     lua_createtable(lstate, 0, 0);
-    ecb.priv = lstate;
     break;
   }
 
@@ -314,8 +387,6 @@ int nlua_xdl_diff(lua_State *lstate)
     }
   }
 
-  XFREE_CLEAR(priv);
-
 exit_0:
   if (ERROR_SET(&err)) {
     luaL_where(lstate, 1);