Merge pull request #4304 from bfredl/yank

Add v:event variable and TextYankPost autocommand

10 files changed, 413 insertions, 28 deletions

diff --git a/clint.py b/clint.py
index 9f6a35b7f4..fc081dcd14 100755
--- a/clint.py
+++ b/clint.py
@@ -2552,7 +2552,7 @@ def CheckBraces(filename, clean_lines, linenum, error):
 
     # If should always have a brace
     for blockstart in ('if', 'while', 'for'):
-        if Match(r'\s*{0}[^{{]*$'.format(blockstart), line):
+        if Match(r'\s*{0}(?!\w)[^{{]*$'.format(blockstart), line):
             pos = line.find(blockstart)
             pos = line.find('(', pos)
             if pos > 0:
diff --git a/runtime/doc/autocmd.txt b/runtime/doc/autocmd.txt
index e17281821c..ec5818e16f 100644
--- a/runtime/doc/autocmd.txt
+++ b/runtime/doc/autocmd.txt
@@ -308,6 +308,8 @@ Name			triggered by ~
 |InsertCharPre|		when a character was typed in Insert mode, before
 			inserting it
 
+|TextYankPost|		when some text is yanked or deleted
+
 |TextChanged|		after a change was made to the text in Normal mode
 |TextChangedI|		after a change was made to the text in Insert mode
 
@@ -722,6 +724,18 @@ InsertCharPre			When a character is typed in Insert mode,
 				It is not allowed to change the text |textlock|.
 				The event is not triggered when 'paste' is
 				set.
+							*TextYankPost*
+TextYankPost			Just after a |yank| or |deleting| command, but not
+				if the black hole register |quote_| is used nor
+				for |setreg()|. Pattern must be * because its
+				meaning may change in the future.
+				Sets these |v:event| keys:
+					operator
+					regcontents
+					regname
+					regtype
+				Recursion is ignored.
+				It is not allowed to change the text |textlock|.
 							*InsertEnter*
 InsertEnter			Just before starting Insert mode.  Also for
 				Replace mode and Virtual Replace mode.  The
diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index ad736e9c81..51e2b505f5 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -1386,6 +1386,22 @@ v:errors	Errors found by assert functions, such as |assert_true()|.
 <		If v:errors is set to anything but a list it is made an empty
 		list by the assert function.
 
+					*v:event* *event-variable*
+v:event		Dictionary of event data for the current |autocommand|.  The
+		available keys differ per event type and are specified at the
+		documentation for each |event|.  The possible keys are:
+			operator	The operation performed.  Unlike
+					|v:operator|, it is set also for an Ex
+					mode command.  For instance, |:yank| is
+					translated to "|y|".
+			regcontents	Text stored in the register as a
+					|readfile()|-style list of lines.
+			regname 	Requested register (e.g "x" for "xyy)
+					or the empty string for an unnamed
+					operation.
+			regtype		Type of register as returned by
+					|getregtype()|.
+
 					*v:exception* *exception-variable*
 v:exception	The value of the exception most recently caught and not
 		finished.  See also |v:throwpoint| and |throw-variables|.
diff --git a/src/nvim/auevents.lua b/src/nvim/auevents.lua
index aa4a8d8332..8d891effae 100644
--- a/src/nvim/auevents.lua
+++ b/src/nvim/auevents.lua
@@ -83,6 +83,7 @@ return {
     'TermResponse',           -- after setting "v:termresponse"
     'TextChanged',            -- text was modified
     'TextChangedI',           -- text was modified in Insert mode
+    'TextYankPost',           -- after a yank or delete was done (y, d, c)
     'User',                   -- user defined autocommand
     'VimEnter',               -- after starting Vim
     'VimLeave',               -- before exiting Vim
diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 76deedfad0..33b8415336 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -378,6 +378,7 @@ static struct vimvar {
   { VV_NAME("option_type",      VAR_STRING), VV_RO },
   { VV_NAME("errors",           VAR_LIST), 0 },
   { VV_NAME("msgpack_types",    VAR_DICT), VV_RO },
+  { VV_NAME("event",            VAR_DICT), VV_RO },
 };
 
 /* shorthand */
@@ -545,6 +546,10 @@ void eval_init(void)
 
   set_vim_var_dict(VV_MSGPACK_TYPES, msgpack_types_dict);
   set_vim_var_dict(VV_COMPLETED_ITEM, dict_alloc());
+
+  dict_T *v_event = dict_alloc();
+  v_event->dv_lock = VAR_FIXED;
+  set_vim_var_dict(VV_EVENT, v_event);
   set_vim_var_list(VV_ERRORS, list_alloc());
   set_vim_var_nr(VV_SEARCHFORWARD, 1L);
   set_vim_var_nr(VV_HLSEARCH, 1L);
@@ -6017,6 +6022,27 @@ static void rettv_dict_alloc(typval_T *rettv)
   ++d->dv_refcount;
 }
 
+/// Clear all the keys of a Dictionary. "d" remains a valid empty Dictionary.
+///
+/// @param d The Dictionary to clear
+void dict_clear(dict_T *d)
+  FUNC_ATTR_NONNULL_ALL
+{
+  hash_lock(&d->dv_hashtab);
+  assert(d->dv_hashtab.ht_locked > 0);
+
+  size_t todo = d->dv_hashtab.ht_used;
+  for (hashitem_T *hi = d->dv_hashtab.ht_array; todo > 0; hi++) {
+    if (!HASHITEM_EMPTY(hi)) {
+      dictitem_free(HI2DI(hi));
+      hash_remove(&d->dv_hashtab, hi);
+      todo--;
+    }
+  }
+
+  hash_unlock(&d->dv_hashtab);
+}
+
 
 /*
  * Unreference a Dictionary: decrement the reference count and free it when it
@@ -6258,6 +6284,24 @@ int dict_add_list(dict_T *d, char *key, list_T *list)
   return OK;
 }
 
+/// Set all existing keys in "dict" as read-only.
+///
+/// This does not protect against adding new keys to the Dictionary.
+///
+/// @param dict The dict whose keys should be frozen
+void dict_set_keys_readonly(dict_T *dict)
+  FUNC_ATTR_NONNULL_ALL
+{
+  size_t todo = dict->dv_hashtab.ht_used;
+  for (hashitem_T *hi = dict->dv_hashtab.ht_array; todo > 0 ; hi++) {
+    if (HASHITEM_EMPTY(hi)) {
+      continue;
+    }
+    todo--;
+    HI2DI(hi)->di_flags |= DI_FLAGS_RO | DI_FLAGS_FIX;
+  }
+}
+
 /*
  * Get the number of items in a Dictionary.
  */
@@ -10579,8 +10623,6 @@ static void f_getregtype(typval_T *argvars, typval_T *rettv)
 {
   char_u      *strregname;
   int regname;
-  char_u buf[NUMBUFLEN + 2];
-  long reglen = 0;
 
   if (argvars[0].v_type != VAR_UNKNOWN) {
     strregname = get_tv_string_chk(&argvars[0]);
@@ -10597,18 +10639,13 @@ static void f_getregtype(typval_T *argvars, typval_T *rettv)
   if (regname == 0)
     regname = '"';
 
-  buf[0] = NUL;
-  buf[1] = NUL;
-  switch (get_reg_type(regname, &reglen)) {
-  case MLINE: buf[0] = 'V'; break;
-  case MCHAR: buf[0] = 'v'; break;
-  case MBLOCK:
-    buf[0] = Ctrl_V;
-    sprintf((char *)buf + 1, "%" PRId64, (int64_t)(reglen + 1));
-    break;
-  }
+  colnr_T reglen = 0;
+  char buf[NUMBUFLEN + 2];
+  char_u reg_type = get_reg_type(regname, &reglen);
+  format_reg_type(reg_type, reglen, buf, ARRAY_SIZE(buf));
+
   rettv->v_type = VAR_STRING;
-  rettv->vval.v_string = vim_strsave(buf);
+  rettv->vval.v_string = (char_u *)xstrdup(buf);
 }
 
 /*
@@ -18162,14 +18199,7 @@ void set_vim_var_dict(int idx, dict_T *val)
   if (val != NULL) {
     ++val->dv_refcount;
     // Set readonly
-    size_t todo = val->dv_hashtab.ht_used;
-    for (hashitem_T *hi = val->dv_hashtab.ht_array; todo > 0 ; ++hi) {
-      if (HASHITEM_EMPTY(hi)) {
-         continue;
-      }
-      --todo;
-      HI2DI(hi)->di_flags = DI_FLAGS_RO | DI_FLAGS_FIX;
-    }
+    dict_set_keys_readonly(val);
   }
 }
 
diff --git a/src/nvim/eval.h b/src/nvim/eval.h
index 79a1341d98..f51b0f4921 100644
--- a/src/nvim/eval.h
+++ b/src/nvim/eval.h
@@ -113,7 +113,8 @@ enum {
     VV_OPTION_TYPE,
     VV_ERRORS,
     VV_MSGPACK_TYPES,
-    VV_LEN, /* number of v: vars */
+    VV_EVENT,
+    VV_LEN,  // number of v: vars
 };
 
 /// Maximum number of function arguments
diff --git a/src/nvim/ops.c b/src/nvim/ops.c
index b1adc85e1d..ab6e0d2e7d 100644
--- a/src/nvim/ops.c
+++ b/src/nvim/ops.c
@@ -19,6 +19,7 @@
 #include "nvim/ex_cmds.h"
 #include "nvim/ex_cmds2.h"
 #include "nvim/ex_getln.h"
+#include "nvim/fileio.h"
 #include "nvim/fold.h"
 #include "nvim/getchar.h"
 #include "nvim/indent.h"
@@ -1409,8 +1410,9 @@ int op_delete(oparg_T *oap)
       op_yank_reg(oap, false, reg, false);
     }
 
-    if(oap->regname == 0) {
+    if (oap->regname == 0) {
       set_clipboard(0, reg);
+      yank_do_autocmd(oap, reg);
     }
 
   }
@@ -2309,6 +2311,8 @@ bool op_yank(oparg_T *oap, bool message)
   yankreg_T *reg = get_yank_register(oap->regname, YREG_YANK);
   op_yank_reg(oap, message, reg, is_append_register(oap->regname));
   set_clipboard(oap->regname, reg);
+  yank_do_autocmd(oap, reg);
+
   return true;
 }
 
@@ -2524,6 +2528,58 @@ static void yank_copy_line(yankreg_T *reg, struct block_def *bd, long y_idx)
   *pnew = NUL;
 }
 
+/// Execute autocommands for TextYankPost.
+///
+/// @param oap Operator arguments.
+/// @param reg The yank register used.
+static void yank_do_autocmd(oparg_T *oap, yankreg_T *reg)
+  FUNC_ATTR_NONNULL_ALL
+{
+  static bool recursive = false;
+
+  if (recursive || !has_event(EVENT_TEXTYANKPOST)) {
+    // No autocommand was defined
+    // or we yanked from this autocommand.
+    return;
+  }
+
+  recursive = true;
+
+  // set v:event to a dictionary with information about the yank
+  dict_T *dict = get_vim_var_dict(VV_EVENT);
+
+  // the yanked text
+  list_T *list = list_alloc();
+  for (linenr_T i = 0; i < reg->y_size; i++) {
+    list_append_string(list, reg->y_array[i], -1);
+  }
+  list->lv_lock = VAR_FIXED;
+  dict_add_list(dict, "regcontents", list);
+
+  // the register type
+  char buf[NUMBUFLEN+2];
+  format_reg_type(reg->y_type, reg->y_width, buf, ARRAY_SIZE(buf));
+  dict_add_nr_str(dict, "regtype", 0, (char_u *)buf);
+
+  // name of requested register or the empty string for an unnamed operation.
+  buf[0] = (char)oap->regname;
+  buf[1] = NUL;
+  dict_add_nr_str(dict, "regname", 0, (char_u *)buf);
+
+  // kind of operation (yank/delete/change)
+  buf[0] = get_op_char(oap->op_type);
+  buf[1] = NUL;
+  dict_add_nr_str(dict, "operator", 0, (char_u *)buf);
+
+  dict_set_keys_readonly(dict);
+  textlock++;
+  apply_autocmds(EVENT_TEXTYANKPOST, NULL, NULL, false, curbuf);
+  textlock--;
+  dict_clear(dict);
+
+  recursive = false;
+}
+
 
 /*
  * Put contents of register "regname" into the text.
@@ -4631,7 +4687,7 @@ theend:
  * Used for getregtype()
  * Returns MAUTO for error.
  */
-char_u get_reg_type(int regname, long *reglen)
+char_u get_reg_type(int regname, colnr_T *reg_width)
 {
   switch (regname) {
   case '%':                     /* file name */
@@ -4654,13 +4710,45 @@ char_u get_reg_type(int regname, long *reglen)
   yankreg_T *reg = get_yank_register(regname, YREG_PASTE);
 
   if (reg->y_array != NULL) {
-    if (reglen != NULL && reg->y_type == MBLOCK)
-      *reglen = reg->y_width;
+    if (reg_width != NULL && reg->y_type == MBLOCK) {
+      *reg_width = reg->y_width;
+    }
     return reg->y_type;
   }
   return MAUTO;
 }
 
+/// Format the register type as a string.
+///
+/// @param reg_type The register type.
+/// @param reg_width The width, only used if "reg_type" is MBLOCK.
+/// @param[out] buf Buffer to store formatted string. The allocated size should
+///                 be at least NUMBUFLEN+2 to always fit the value.
+/// @param buf_len The allocated size of the buffer.
+void format_reg_type(char_u reg_type, colnr_T reg_width,
+                     char* buf, size_t buf_len)
+  FUNC_ATTR_NONNULL_ALL
+{
+  assert(buf_len > 1);
+  switch (reg_type) {
+    case MLINE:
+      buf[0] = 'V';
+      buf[1] = NUL;
+      break;
+    case MCHAR:
+      buf[0] = 'v';
+      buf[1] = NUL;
+      break;
+    case MBLOCK:
+      snprintf(buf, buf_len, CTRL_V_STR "%" PRIdCOLNR, reg_width + 1);
+      break;
+    case MAUTO:
+      buf[0] = NUL;
+      break;
+  }
+}
+
+
 /// When `flags` has `kGRegList` return a list with text `s`.
 /// Otherwise just return `s`.
 ///
diff --git a/src/nvim/pos.h b/src/nvim/pos.h
index 7071df51e8..864f3fe866 100644
--- a/src/nvim/pos.h
+++ b/src/nvim/pos.h
@@ -2,7 +2,11 @@
 #define NVIM_POS_H
 
 typedef long linenr_T;         // line number type
-typedef int colnr_T;           // column number type
+
+/// Column number type
+typedef int colnr_T;
+/// Format used to print values which have colnr_T type
+#define PRIdCOLNR "d"
 
 #define MAXLNUM 0x7fffffff     // maximum (invalid) line number
 #define MAXCOL  0x7fffffff     // maximum column number, 31 bits
diff --git a/test/functional/autocmd/textyankpost_spec.lua b/test/functional/autocmd/textyankpost_spec.lua
new file mode 100644
index 0000000000..965b19581a
--- /dev/null
+++ b/test/functional/autocmd/textyankpost_spec.lua
@@ -0,0 +1,216 @@
+local helpers = require('test.functional.helpers')
+local clear, eval, eq, insert = helpers.clear, helpers.eval, helpers.eq, helpers.insert
+local feed, execute, expect, command = helpers.feed, helpers.execute, helpers.expect, helpers.command
+local curbufmeths, funcs, neq = helpers.curbufmeths, helpers.funcs, helpers.neq
+
+describe('TextYankPost', function()
+  before_each(function()
+    clear()
+
+    -- emulate the clipboard so system clipboard isn't affected
+    execute('let &rtp = "test/functional/fixtures,".&rtp')
+
+    execute('let g:count = 0')
+    execute('autocmd TextYankPost * let g:event = copy(v:event)')
+    execute('autocmd TextYankPost * let g:count += 1')
+
+    curbufmeths.set_line_slice(0, -1, true, true, {
+      'foo\0bar',
+      'baz text',
+    })
+  end)
+
+  it('is executed after yank and handles register types', function()
+    feed('yy')
+    eq({
+      operator = 'y',
+      regcontents = { 'foo\nbar' },
+      regname = '',
+      regtype = 'V'
+    }, eval('g:event'))
+    eq(1, eval('g:count'))
+
+    -- v:event is cleared after the autocommand is done
+    eq({}, eval('v:event'))
+
+    feed('+yw')
+    eq({
+      operator = 'y',
+      regcontents = { 'baz ' },
+      regname = '',
+      regtype = 'v'
+    }, eval('g:event'))
+    eq(2, eval('g:count'))
+
+    feed('<c-v>eky')
+    eq({
+      operator = 'y',
+      regcontents = { 'foo', 'baz' },
+      regname = '',
+      regtype = "\0223" -- ^V + block width
+    }, eval('g:event'))
+    eq(3, eval('g:count'))
+  end)
+
+  it('makes v:event immutable', function()
+    feed('yy')
+    eq({
+      operator = 'y',
+      regcontents = { 'foo\nbar' },
+      regname = '',
+      regtype = 'V'
+    }, eval('g:event'))
+
+    execute('set debug=msg')
+    -- the regcontents should not be changed without copy.
+    local status, err = pcall(command,'call extend(g:event.regcontents, ["more text"])')
+    eq(status,false)
+    neq(nil, string.find(err, ':E742:'))
+
+    -- can't mutate keys inside the autocommand
+    execute('autocmd! TextYankPost * let v:event.regcontents = 0')
+    status, err = pcall(command,'normal yy')
+    eq(status,false)
+    neq(nil, string.find(err, ':E46:'))
+
+    -- can't add keys inside the autocommand
+    execute('autocmd! TextYankPost * let v:event.mykey = 0')
+    status, err = pcall(command,'normal yy')
+    eq(status,false)
+    neq(nil, string.find(err, ':E742:'))
+  end)
+
+  it('is not invoked recursively', function()
+    execute('autocmd TextYankPost * normal "+yy')
+    feed('yy')
+    eq({
+      operator = 'y',
+      regcontents = { 'foo\nbar' },
+      regname = '',
+      regtype = 'V'
+    }, eval('g:event'))
+    eq(1, eval('g:count'))
+    eq({ 'foo\nbar' }, funcs.getreg('+',1,1))
+  end)
+
+  it('is executed after delete and change', function()
+    feed('dw')
+    eq({
+      operator = 'd',
+      regcontents = { 'foo' },
+      regname = '',
+      regtype = 'v'
+    }, eval('g:event'))
+    eq(1, eval('g:count'))
+
+    feed('dd')
+    eq({
+      operator = 'd',
+      regcontents = { '\nbar' },
+      regname = '',
+      regtype = 'V'
+    }, eval('g:event'))
+    eq(2, eval('g:count'))
+
+    feed('cwspam<esc>')
+    eq({
+      operator = 'c',
+      regcontents = { 'baz' },
+      regname = '',
+      regtype = 'v'
+    }, eval('g:event'))
+    eq(3, eval('g:count'))
+  end)
+
+  it('is not executed after black-hole operation', function()
+    feed('"_dd')
+    eq(0, eval('g:count'))
+
+    feed('"_cwgood<esc>')
+    eq(0, eval('g:count'))
+
+    expect([[
+      good text]])
+    feed('"_yy')
+    eq(0, eval('g:count'))
+
+    execute('delete _')
+    eq(0, eval('g:count'))
+  end)
+
+  it('gives the correct register name', function()
+    feed('$"byiw')
+    eq({
+      operator = 'y',
+      regcontents = { 'bar' },
+      regname = 'b',
+      regtype = 'v'
+    }, eval('g:event'))
+
+    feed('"*yy')
+    eq({
+      operator = 'y',
+      regcontents = { 'foo\nbar' },
+      regname = '*',
+      regtype = 'V'
+    }, eval('g:event'))
+
+    execute("set clipboard=unnamed")
+
+    -- regname still shows the name the user requested
+    feed('yy')
+    eq({
+      operator = 'y',
+      regcontents = { 'foo\nbar' },
+      regname = '',
+      regtype = 'V'
+    }, eval('g:event'))
+
+    feed('"*yy')
+    eq({
+      operator = 'y',
+      regcontents = { 'foo\nbar' },
+      regname = '*',
+      regtype = 'V'
+    }, eval('g:event'))
+  end)
+
+  it('works with Ex commands', function()
+    execute('1delete +')
+    eq({
+      operator = 'd',
+      regcontents = { 'foo\nbar' },
+      regname = '+',
+      regtype = 'V'
+    }, eval('g:event'))
+    eq(1, eval('g:count'))
+
+    execute('yank')
+    eq({
+      operator = 'y',
+      regcontents = { 'baz text' },
+      regname = '',
+      regtype = 'V'
+    }, eval('g:event'))
+    eq(2, eval('g:count'))
+
+    execute('normal yw')
+    eq({
+      operator = 'y',
+      regcontents = { 'baz ' },
+      regname = '',
+      regtype = 'v'
+    }, eval('g:event'))
+    eq(3, eval('g:count'))
+
+    execute('normal! dd')
+    eq({
+      operator = 'd',
+      regcontents = { 'baz text' },
+      regname = '',
+      regtype = 'V'
+    }, eval('g:event'))
+    eq(4, eval('g:count'))
+  end)
+
+end)
diff --git a/test/functional/eval/vvar_event_spec.lua b/test/functional/eval/vvar_event_spec.lua
new file mode 100644
index 0000000000..bbac86524f
--- /dev/null
+++ b/test/functional/eval/vvar_event_spec.lua
@@ -0,0 +1,15 @@
+local helpers = require('test.functional.helpers')
+local clear, eval, eq = helpers.clear, helpers.eval, helpers.eq
+local command = helpers.command
+describe('v:event', function()
+  before_each(clear)
+  it('is empty before any autocommand', function()
+    eq({}, eval('v:event'))
+  end)
+
+  it('is immutable', function()
+    eq(false, pcall(command, 'let v:event = {}'))
+    eq(false, pcall(command, 'let v:event.mykey = {}'))
+  end)
+end)
+