Merge remote-tracking branch 'm-kru/vhdl' into master

8 files changed, 481 insertions, 65 deletions

diff --git a/rc/filetype/rust.kak b/rc/filetype/rust.kak
index 8588789e..3db474d7 100644
--- a/rc/filetype/rust.kak
+++ b/rc/filetype/rust.kak
@@ -36,10 +36,10 @@ add-highlighter shared/rust/string           region %{(?<!')"} (?<!\\)(\\\\)*"
 add-highlighter shared/rust/raw_string       region -match-capture %{(?<!')r(#*)"} %{"(#*)} fill string
 
 add-highlighter shared/rust/line_doctest region ^\h*//[!/]\h*```($|should_panic|no_run|ignore|allow_fail|rust|test_harness|compile_fail|E\d{4}|edition201[58]) ^\h*//[!/]\h*```$ regions
-add-highlighter shared/rust/line_doctest/marker region ```.* $ group
+add-highlighter shared/rust/line_doctest/marker region ``` $ group
 add-highlighter shared/rust/line_doctest/marker/fence regex ``` 0:meta
 add-highlighter shared/rust/line_doctest/marker/keywords regex [\d\w] 0:meta # already matched above, just ignore comma
-add-highlighter shared/rust/line_doctest/inner region '^\h*//[!/]( #(?= )|)' '$| ' group
+add-highlighter shared/rust/line_doctest/inner region '^\h*//[!/]( #(?= ))?' '$| ' group
 add-highlighter shared/rust/line_doctest/inner/comment regex //[!/] 0:documentation
 add-highlighter shared/rust/line_doctest/inner/hidden regex '#' 0:meta
 add-highlighter shared/rust/line_doctest/code default-region ref rust
@@ -51,7 +51,7 @@ add-highlighter shared/rust/line_comment1    region // $
 add-highlighter shared/rust/block_comment2   region -recurse /\*\*\* /\*\*\* \*/            fill comment
 add-highlighter shared/rust/block_doc        region -recurse /\*\* /\*\* \*/ regions
 add-highlighter shared/rust/block_doc/doctest region ```($|should_panic|no_run|ignore|allow_fail|rust|test_harness|compile_fail|E\d{4}|edition201[58]) ```$ regions
-add-highlighter shared/rust/block_doc/doctest/marker region ```.* $ group
+add-highlighter shared/rust/block_doc/doctest/marker region ``` $ group
 add-highlighter shared/rust/block_doc/doctest/marker/fence regex ``` 0:meta
 add-highlighter shared/rust/block_doc/doctest/marker/keywords regex [\d\w] 0:meta # already matched above, just ignore comma
 add-highlighter shared/rust/block_doc/doctest/inner default-region group
diff --git a/rc/filetype/vhdl.kak b/rc/filetype/vhdl.kak
new file mode 100644
index 00000000..93108d2f
--- /dev/null
+++ b/rc/filetype/vhdl.kak
@@ -0,0 +1,408 @@
+# Based on IEEE Std 1076‐2019
+
+# Detection
+hook global BufCreate .*[.](vhd[l]?) %[
+	set-option buffer filetype vhdl
+]
+
+# Initialization
+hook global WinSetOption filetype=vhdl %[
+	require-module vhdl
+	set-option window static_words %opt{vhdl_static_words}
+	hook -group vhdl-indent window InsertChar \n  vhdl-indent-on-new-line
+	hook -group vhdl-indent window InsertChar \)  vhdl-indent-on-closing-parenthesis
+	hook -group vhdl-insert window InsertChar \n  vhdl-insert-on-new-line
+	# Cleanup trailing whitespaces on current line insert end.
+	hook -group vhdl-trim-indent window ModeChange pop:insert:.* %[ try %[ execute-keys -draft <semicolon> <a-x> s ^\h+$ <ret> d ] ]
+	hook -once -always window WinSetOption filetype=.* %[ remove-hooks window vhdl-.+ ]
+]
+
+hook -group vhdl-highlight global WinSetOption filetype=vhdl %[
+	add-highlighter window/vhdl ref vhdl
+	hook -once -always window WinSetOption filetype=.* %[ remove-highlighter window/vhdl ]
+]
+
+provide-module vhdl %§
+
+# Highlighters & Completion
+add-highlighter shared/vhdl regions
+add-highlighter shared/vhdl/code default-region group
+add-highlighter shared/vhdl/comment_line region '--' $ fill comment
+add-highlighter shared/vhdl/comment region /\* \*/ fill comment
+
+# Integer formats
+add-highlighter shared/vhdl/code/ regex '(?i)\b0b[01]+l?\b' 0:value
+add-highlighter shared/vhdl/code/ regex '(?i)\b0x[\da-f]+l?\b' 0:value
+add-highlighter shared/vhdl/code/ regex '(?i)\b0o?[0-7]+l?\b' 0:value
+add-highlighter shared/vhdl/code/ regex '(?i)\b([1-9]\d*|0)l?\b' 0:value
+# Float formats
+add-highlighter shared/vhdl/code/ regex '\b\d+[eE][+-]?\d+\b' 0:value
+add-highlighter shared/vhdl/code/ regex '(\b\d+)?\.\d+\b' 0:value
+add-highlighter shared/vhdl/code/ regex '\b\d+\.' 0:value
+# Imaginary formats
+add-highlighter shared/vhdl/code/ regex '\b\d+\+\d+[jJ]\b' 0:value
+
+evaluate-commands %sh[
+	values="true false note warning error failure"
+
+	# LRM 5.2.4.1
+	units="fs ps ns us ms sec min Å nm um mm cm m km"
+
+	# LRM 16.2
+	predefined_attributes="
+		base left right high low ascending length range reverse_range
+		subtype image pos succ pred leftof rightof value val
+		designated_subtype reflect high low index element delayed
+		stable quiet transaction event active last_event last_active
+		last_value driving driving_value simple_name instance_name
+		path_name record signal converse
+	"
+
+	libraries="ieee std"
+
+	packages="
+		math_real math_complex std_logic_1164 std_logic_textio numeric_bit numeric_std
+		numeric_bit_unsigned numeric_std_unsigned fixed_float_types fixed_generic_pkg
+		fixed_pkg float_generic_pkg float_pkg
+		standard textio env
+	"
+
+	 # LRM 15.10
+	reserved_words="
+		abs access after alias all and architecture array assert assume assume_guarantee attribute
+		begin block body buffer bus
+		case component configuration constant context cover
+		default disconnect downto
+		else elsif end entity exit
+		fairness file for force function
+		generate generic group guarded
+		if impure in inertial inout is
+		label library linkage literal loop
+		map mod
+		nand new next nor not null
+		of on open or others out
+		package parameter port postponed procedure process property protected pure
+		range record register reject release rem report restrict restrict_guarantee return rol ror
+		select sequence severity signal shared sla sll sra srl strong subtype
+		then to transport type
+		unaffected units until use
+		variable view vpkg vmode vprop vunit
+		wait when while with
+		xnor xor
+	"
+
+	types="
+		bit bit_vector
+		boolean
+		file_open_state file_origin_kind
+		integer natural positive
+		line line_vector
+		std_logic std_logic_vector
+		std_ulogic std_ulogic_vector
+		side
+		signed unsigned
+		string text
+		time
+	"
+
+	functions="
+		find_leftmost find_rightmost divide reciprocal remainder modulo minimum maximum
+		std_match add_carry scalb
+		resize to_ufixed to_sfixed to_unsigned to_signed to_real to_integer to_slv
+		to_std_logic_vector to_stdlogicvector to_sulv to_std_ulogic_vector to_std_ulogicvector
+		to_01 is_x to_x01 to_ux01 to_x01z
+		ufixed_high ufixed_low sfixed_high sfixed_low to_ufix to_sfix ufix_high ufix_low
+		sfix_high sfix_low
+		write read bwrite binary_write bread binary_read owrite oread octal_write octal_read
+		hwrite hread hex_write hex_read to_string to_bstring to_binary_string to_ostring
+		to_octal_string to_hstring to_hex_string from_string from_bstring from_binary_string
+		from_ostring from_octal_string from_hstring from_hex_string
+		rising_edge falling_edge
+	"
+
+	join() { sep=$2; eval set -- $1; IFS="$sep"; echo "$*"; }
+
+	# Add the language's grammar to the static completion list
+	printf %s\\n "declare-option str-list vhdl_static_words $(join "${values} ${units} ${predefined_attributes} ${libraries} ${packages} ${reserved_words} ${types} ${functions}" ' ')"
+
+	 # Highlight keywords
+	printf %s "
+		add-highlighter shared/vhdl/code/ regex '(?i)\b($(join "${values}" '|'))\b' 0:value
+		add-highlighter shared/vhdl/code/ regex '(?i)\b($(join "${units}" '|'))\b' 0:meta
+		add-highlighter shared/vhdl/code/ regex \"'(?i)\b($(join "${predefined_attributes}" '|'))\b\" 0:attribute
+		add-highlighter shared/vhdl/code/ regex '(?i)\b($(join "${libraries}" '|'))\b' 0:builtin
+		add-highlighter shared/vhdl/code/ regex '(?i)\b($(join "${packages}" '|'))\b' 0:builtin
+		add-highlighter shared/vhdl/code/ regex '(?i)\b($(join "${reserved_words}" '|'))\b' 0:keyword
+		add-highlighter shared/vhdl/code/ regex '(?i)\b($(join "${functions}" '|'))\b\(' 1:builtin
+		add-highlighter shared/vhdl/code/ regex '(?i)\b($(join "${types}" '|'))\b' 0:type
+		add-highlighter shared/vhdl/code/ regex '^\h*(@[\w_.]+))' 1:attribute
+	"
+]
+
+add-highlighter shared/vhdl/code/ regex \(|\)|\;|\.|,|:|\| 0:attribute
+
+add-highlighter shared/vhdl/code/ regex \?\?|=|/=|<|<=|>|>=|\?=|\?/=|\?<|\?<=|\?>|\?>=|\+|-|&|\*|/|:= 0:operator
+
+# Meta values highlight.
+# The values 'U', 'X', 'W', and '–' are metalogical values; they define the behavior of the model itself rather than the behavior of the hardware being synthesized.
+add-highlighter shared/vhdl/code/ regex "(?i)'[U|X|W|-]'" 0:meta
+# Highlight other logical values.
+add-highlighter shared/vhdl/code/ regex "(?i)'[0|1|Z|L|H]'" 0:value
+
+# String
+add-highlighter shared/vhdl/code/ regex '"[^"]*"' 0:string
+
+# Binary vector.
+add-highlighter shared/vhdl/code/ regex '[bB]"[01_]*"' 0:value
+
+# Octal vector.
+add-highlighter shared/vhdl/code/ regex '[oO]"[01234567_]*"' 0:value
+
+# Hex vector.
+add-highlighter shared/vhdl/code/ regex '(?i)x"[0123456789abcdef_]*"' 0:value
+
+define-command -hidden vhdl-insert-on-new-line %[
+	# Handle comment lines.
+	evaluate-commands -itersel %[
+		# Copy '--' comment prefix and following white spaces.
+		try %[
+			# <a-lt> is needed because of "Preserve previous line indent" command.
+			try %[ execute-keys -draft k <a-x> s ^\h*--\h* <ret> y j <a-lt> gh P ]
+		]
+	]
+
+	evaluate-commands -save-regs x %[
+		# Save previous line indent in register x.
+		try %[ execute-keys -draft k<a-x>s^\h+<ret>"xy ] catch %[ reg x '' ]
+
+		# All "wisely add" commands share the same concept.
+		# Only "end if" has extra comments.
+		# Wisely add "end if;".
+		evaluate-commands %[
+			try %[
+				# Validate previous line and that it is not closed yet.
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)((then|(.*:\h*)?if\b.*\bthen)$)<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(else|end|elsif)\b<ret>
+				# Don't add for "if ... generate", it requires "end generate;".
+				execute-keys -draft k<a-x> <a-K>(?i)\bgenerate\b<ret>
+				execute-keys -draft o<c-r>xend<space>if<semicolon><esc>
+			]
+		]
+		# Wisely add "end generate;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i).*\bgenerate$<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(begin|end)<ret>
+				# Don't add in case of comment line.
+				execute-keys -draft k<a-x> <a-K>^\h*--<ret>
+				execute-keys -draft o<c-r>xend<space>generate<semicolon><esc>
+			]
+		]
+		# Wisely add "end case;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)(case|.*\h*:\h*case)\b<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)end<ret>
+				execute-keys -draft o<c-r>xend<space>case<semicolon><esc>
+			]
+		]
+		# Wisely add "begin" and "end block;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)((block|.*:\h*block)\b)<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(begin|end)<ret>
+				execute-keys -draft o<c-r>xbegin<ret><c-r>xend<space>block<semicolon><esc>
+			]
+		]
+		# Wisely add "begin" and "end process;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)(.*:\h*)?(postponed\h+)?process\b<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(begin|end)<ret>
+				execute-keys -draft o<c-r>xbegin<ret><c-r>xend<space>process<semicolon><esc>
+			]
+		]
+		# Wisely add "end loop;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)(.*\bloop|.*\h*:\h*(for|loop))$<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(end)<ret>
+				execute-keys -draft o<c-r>xend<space>loop<semicolon><esc>
+			]
+		]
+		# Wisely add "end protected;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)(type\b.*\bis\h+protected)$<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(end)<ret>
+				execute-keys -draft o<c-r>xend<space>protected<semicolon><esc>
+			]
+		]
+		# Wisely add "end record;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)(type\b.*\bis\h+record\h*)$<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(end)<ret>
+				execute-keys -draft o<c-r>xend<space>record<semicolon><esc>
+			]
+		]
+		# Wisely add ");" for "type ... is (".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)(type\b.*\bis\h+\(\h*)$<ret> J}iJ<a-x> <a-K>^<c-r>x(\))<ret>
+				execute-keys -draft o<c-r>x)<semicolon><esc>
+			]
+		]
+		# Wisely add "end entity;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^(?i)\h*entity\b.*\bis$<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(begin|end)<ret>
+				execute-keys -draft o<c-r>xend<space>entity<semicolon><esc>
+			]
+		]
+		# Wisely add "begin" and "end function;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^(?i)(\h*\)?\h*return\b.*\bis$)<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(begin|end)<ret>
+				execute-keys -draft o<c-r>xbegin<ret><c-r>xend<space>function<semicolon><esc>
+			]
+			try %[
+				execute-keys -draft k<a-x> <a-k>^(?i)(\h*((pure|impure)\h+)?function\b.*\bis$)<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(begin|end)<ret>
+				execute-keys -draft o<c-r>xbegin<ret><c-r>xend<space>function<semicolon><esc>
+			]
+		]
+		# Wisely add "begin" and "end procedure;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^(?i)(\h*procedure\b.*\bis$)<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)\b(begin|end)\b<ret>
+				execute-keys -draft o<c-r>xbegin<ret><c-r>xend<space>procedure<semicolon><esc>
+			]
+			try %[
+			execute-keys -draft k<a-x> <a-k>^(?i)\h*\)\h*\bis$<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)\b(begin|end)\b<ret>
+			# Verify that line with opening parenthesis contains "procedure" keyword.
+			execute-keys -draft k<a-x> s\)<ret> <a-m><semicolon> <a-x><a-k> (?i)\bprocedure\b<ret>
+			execute-keys -draft o<c-r>xbegin<ret><c-r>xend<space>procedure<semicolon><esc>
+			]
+		]
+		# Wisely add "end package;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^(?i)(package\b)<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(end)<ret>
+				# Make sure it is not package body.
+				execute-keys -draft k<a-x><a-K>(?i)\bbody\b<ret>
+				execute-keys -draft oend<space>package<semicolon><esc>
+			]
+		]
+		# Wisely add "end package body;".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^(?i)(package\h+body\b)<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(end)<ret>
+				execute-keys -draft oend<space>package<space>body<semicolon><esc>
+			]
+		]
+		# Wisely add "begin" and "end architecture;".
+		evaluate-commands %[
+			try %[
+			execute-keys -draft k<a-x> <a-k>^(?i)\h*architecture\b<ret> J}iJ<a-x> <a-K>^<c-r>x(?i)(begin|end)<ret>
+			execute-keys -draft o<c-r>xbegin<ret><c-r>xend<space>architecture<semicolon><esc>
+			]
+		]
+		# Wisely add ");" for "port (".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)port\h*\($<ret> J}iJ<a-x> <a-K>^<c-r>x(\)\;)<ret>
+				execute-keys -draft o<c-r>x)<semicolon><esc>
+			]
+		]
+		# Wisely add ");" for "port map (".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)port\h+map\h*\($<ret> J}iJ<a-x> <a-K>^<c-r>x(\)\;)<ret>
+				execute-keys -draft o<c-r>x)<semicolon><esc>
+			]
+		]
+		# Wisely add ");" for "generic (".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)generic\h*\($<ret> J}iJ<a-x> <a-K>^<c-r>x(\)\;)<ret>
+				execute-keys -draft o<c-r>x)<semicolon><esc>
+			]
+		]
+		# Wisely add ")" for "generic map (".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)generic\h+map\h*\($<ret> J}iJ<a-x> <a-K>^<c-r>x(\))<ret>
+				execute-keys -draft o<c-r>x)<esc>
+			]
+		]
+		# Wisely add ") return ;" for "[pure|impure] function ... (".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)(pure\b|impure\b)?\h*function\b.*\h*\($<ret> J}iJ<a-x> <a-K>^<c-r>x(\)\h*return.*)<ret>
+				execute-keys -draft o<c-r>x)<space>return<space><semicolon><esc>
+			]
+		]
+		# Wisely add ");" for "procedure ... (".
+		evaluate-commands %[
+			try %[
+				execute-keys -draft k<a-x> <a-k>^\h*(?i)procedure\b.*\h*\($<ret> J}iJ<a-x> <a-K>^<c-r>x(\)\h*\;)<ret>
+				execute-keys -draft o<c-r>x)<semicolon><esc>
+			]
+		]
+	]
+]
+
+define-command -hidden vhdl-indent-on-new-line %{
+	evaluate-commands -itersel %{
+		# Align "then" to previous "if|elsif".
+		evaluate-commands -itersel -save-regs x %[
+			try %[
+				execute-keys -draft k <a-x> <a-k> (?i)^\h*then$ <ret>
+				try %[ execute-keys -draft <a-/>(?i)\b(if|elsif)\b<ret><a-x>s^\h+<ret>"xy ] catch %[ reg x '' ]
+				try %[ execute-keys -draft k <a-x>s^\h+<ret>d ] catch %[ ]
+				execute-keys -draft kgh i<c-r>x<esc>
+			]
+		]
+
+		 # Align "generate" to previous "if|for".
+		evaluate-commands -itersel -save-regs x %[
+			try %[
+				execute-keys -draft k <a-x> <a-k> (?i)^\h*generate$ <ret>
+				try %[ execute-keys -draft <a-/>(?i)\b(if|for)\b<ret><a-x>s^\h+<ret>"xy ] catch %[ reg x '' ]
+				try %[ execute-keys -draft k <a-x>s^\h+<ret>d ] catch %[ ]
+				execute-keys -draft kgh i<c-r>x<esc>
+			]
+		]
+
+		 # Preserve previous line indent.
+		try %[ execute-keys -draft <semicolon> K <a-&> ]
+
+		 # Cleanup trailing whitespaces from previous line.
+		try %[ execute-keys -draft k <a-x> s \h+$ <ret> d ]
+
+		 # Increase indent after some keywords.
+		try %[
+			execute-keys -draft k<a-x><a-k> (?i)\b(begin|block|else|for|generate|if|is|loop|process|protected|record|select|then)$ <ret>
+			# Does not indent if in comment line.
+			execute-keys -draft k<a-x><a-K>(?i)^\h*--<ret>
+			# Handle case line in a bit different way.
+			execute-keys -draft k<a-x><a-K>(?i)^\h*case\b<ret>
+			execute-keys -draft <semicolon> <a-gt>
+		]
+
+		# Add "when " and increase indent after "case ... is".
+		try %[
+			execute-keys -draft k<a-x><a-k> (?i)\h*case\b.*\h+is$ <ret>
+			# Don't indent if in comment line.
+			execute-keys -draft k<a-x><a-K>(?i)^\h*--<ret>
+			execute-keys -draft <semicolon>iwhen<space><esc><a-gt>
+		]
+
+		# Copy the indentation of the matching if.
+		try %{ execute-keys -draft <space> k <a-x> <a-k> ^\h*(elsif\b|else$) <ret> gh [c^\h*(\S*\h*:\h*)?if\b,\bend\sif\b <ret> <a-x> <a-S> 1<a-&> <space> j K <a-&> }
+
+		# Increase indent after some operators.
+		try %[ execute-keys -draft <semicolon> <space> k <a-x> <a-k> (\(|=>|<=|:=)$ <ret> j <a-gt> ]
+	 }
+}
+
+define-command vhdl-indent-on-closing-parenthesis %[
+	evaluate-commands -itersel %[
+		# Decrease indent after ")" at the beginning of line.
+		try %[ execute-keys -draft <a-x> <a-k> (^\h+\)$) <ret> <a-lt> ]
+	]
+]
+
+§
diff --git a/src/highlighters.cc b/src/highlighters.cc
index 78099b08..309ade94 100644
--- a/src/highlighters.cc
+++ b/src/highlighters.cc
@@ -1744,7 +1744,8 @@ void insert_matches(const Buffer& buffer, RegexMatchList& matches, const Regex&
     for (auto line = range.begin; line < range.end; ++line)
     {
         const StringView l = buffer[line];
-        for (auto&& m : RegexIterator{l.begin(), l.end(), vm})
+        const auto flags = RegexExecFlags::NotEndOfLine; // buffer line already ends with \n
+        for (auto&& m : RegexIterator{l.begin(), l.end(), vm, flags})
         {
             const bool with_capture = capture and m[1].matched and
                                       m[0].second - m[0].first < std::numeric_limits<uint16_t>::max();
diff --git a/src/insert_completer.cc b/src/insert_completer.cc
index 94c1a95e..03ce45a5 100644
--- a/src/insert_completer.cc
+++ b/src/insert_completer.cc
@@ -261,76 +261,74 @@ InsertCompletion complete_option(const SelectionList& sels,
     auto& desc = opt.prefix;
     static const Regex re(R"((\d+)\.(\d+)(?:\+(\d+))?@(\d+))");
     MatchResults<String::const_iterator> match;
-    if (regex_match(desc.begin(), desc.end(), match, re))
-    {
-        BufferCoord coord{ str_to_int({match[1].first, match[1].second}) - 1,
-                         str_to_int({match[2].first, match[2].second}) - 1 };
-        if (not buffer.is_valid(coord))
-            return {};
-        size_t timestamp = (size_t)str_to_int({match[4].first, match[4].second});
-        auto changes = buffer.changes_since(timestamp);
-        if (any_of(changes, [&](auto&& change) { return change.begin < coord; }))
-            return {};
-
-        if (cursor_pos.line == coord.line and cursor_pos.column >= coord.column)
-        {
-            StringView query = buffer.substr(coord, cursor_pos);
+    if (not regex_match(desc.begin(), desc.end(), match, re))
+        return {};
 
-            const ColumnCount tabstop = options["tabstop"].get<int>();
-            const ColumnCount column = get_column(buffer, tabstop, cursor_pos);
+    BufferCoord coord{str_to_int({match[1].first, match[1].second}) - 1,
+                      str_to_int({match[2].first, match[2].second}) - 1};
+    if (not buffer.is_valid(coord))
+        return {};
+    size_t timestamp = (size_t)str_to_int({match[4].first, match[4].second});
+    auto changes = buffer.changes_since(timestamp);
+    if (any_of(changes, [&](auto&& change) { return change.begin < coord; }))
+        return {};
 
-            struct RankedMatchAndInfo : RankedMatch
-            {
-                using RankedMatch::RankedMatch;
-                using RankedMatch::operator==;
-                using RankedMatch::operator<;
+    if (cursor_pos.line != coord.line or cursor_pos.column < coord.column)
+        return {};
 
-                StringView on_select;
-                DisplayLine menu_entry;
-            };
+    const ColumnCount tabstop = options["tabstop"].get<int>();
+    const ColumnCount column = get_column(buffer, tabstop, cursor_pos);
 
-            Vector<RankedMatchAndInfo> matches;
+    struct RankedMatchAndInfo : RankedMatch
+    {
+        using RankedMatch::RankedMatch;
+        using RankedMatch::operator==;
+        using RankedMatch::operator<;
 
-            for (auto& candidate : opt.list)
-            {
-                if (RankedMatchAndInfo match{std::get<0>(candidate), query})
-                {
-                    match.on_select = std::get<1>(candidate);
-                    auto& menu = std::get<2>(candidate);
-                    match.menu_entry = not menu.empty() ?
-                        parse_display_line(expand_tabs(menu, tabstop, column), faces)
-                      : DisplayLine{ expand_tabs(menu, tabstop, column), {} };
-
-                    matches.push_back(std::move(match));
-                }
-            }
+        StringView on_select;
+        DisplayLine menu_entry;
+    };
 
-            constexpr size_t max_count = 100;
-            // Gather best max_count matches
-            auto greater = [](auto& lhs, auto& rhs) { return rhs < lhs; };
-            auto first = matches.begin(), last = matches.end();
-            std::make_heap(first, last, greater);
-            InsertCompletion::CandidateList candidates;
-            candidates.reserve(std::min(matches.size(), max_count));
-            candidates.reserve(matches.size());
-            while (candidates.size() < max_count and first != last)
-            {
-                if (candidates.empty() or candidates.back().completion != first->candidate())
-                    candidates.push_back({ first->candidate().str(), first->on_select.str(),
-                                           std::move(first->menu_entry) });
-                std::pop_heap(first, last--, greater);
-            }
+    StringView query = buffer.substr(coord, cursor_pos);
+    Vector<RankedMatchAndInfo> matches;
 
-            auto end = cursor_pos;
-            if (match[3].matched)
-            {
-                ByteCount len = str_to_int({match[3].first, match[3].second});
-                end = buffer.advance(coord, len);
-            }
-            return { std::move(candidates), coord, end, timestamp };
+    for (auto& candidate : opt.list)
+    {
+        if (RankedMatchAndInfo match{std::get<0>(candidate), query})
+        {
+            match.on_select = std::get<1>(candidate);
+            auto& menu = std::get<2>(candidate);
+            match.menu_entry = not menu.empty() ?
+                parse_display_line(expand_tabs(menu, tabstop, column), faces)
+              : DisplayLine{String{}, {}};
+
+            matches.push_back(std::move(match));
         }
     }
-    return {};
+
+    constexpr size_t max_count = 100;
+    // Gather best max_count matches
+    auto greater = [](auto& lhs, auto& rhs) { return rhs < lhs; };
+    auto first = matches.begin(), last = matches.end();
+    std::make_heap(first, last, greater);
+    InsertCompletion::CandidateList candidates;
+    candidates.reserve(std::min(matches.size(), max_count));
+    candidates.reserve(matches.size());
+    while (candidates.size() < max_count and first != last)
+    {
+        if (candidates.empty() or candidates.back().completion != first->candidate())
+            candidates.push_back({ first->candidate().str(), first->on_select.str(),
+                                   std::move(first->menu_entry) });
+        std::pop_heap(first, last--, greater);
+    }
+
+    auto end = cursor_pos;
+    if (match[3].matched)
+    {
+        ByteCount len = str_to_int({match[3].first, match[3].second});
+        end = buffer.advance(coord, len);
+    }
+    return { std::move(candidates), coord, end, timestamp };
 }
 
 template<bool other_buffers>
diff --git a/test/regression/3799-incorrect-region-match/cmd b/test/regression/3799-incorrect-region-match/cmd
new file mode 100644
index 00000000..8b137891
--- /dev/null
+++ b/test/regression/3799-incorrect-region-match/cmd
@@ -0,0 +1 @@
+
diff --git a/test/regression/3799-incorrect-region-match/in b/test/regression/3799-incorrect-region-match/in
new file mode 100644
index 00000000..0956e089
--- /dev/null
+++ b/test/regression/3799-incorrect-region-match/in
@@ -0,0 +1,4 @@
+print << "";
+part of heredoc
+
+not part of heredoc
diff --git a/test/regression/3799-incorrect-region-match/rc b/test/regression/3799-incorrect-region-match/rc
new file mode 100644
index 00000000..3e1998b7
--- /dev/null
+++ b/test/regression/3799-incorrect-region-match/rc
@@ -0,0 +1,2 @@
+add-highlighter global/regions regions
+add-highlighter global/regions/heredoc region -match-capture <<\h*"(\w*)" ^(\w*)$ fill red
diff --git a/test/regression/3799-incorrect-region-match/script b/test/regression/3799-incorrect-region-match/script
new file mode 100644
index 00000000..ec4075b4
--- /dev/null
+++ b/test/regression/3799-incorrect-region-match/script
@@ -0,0 +1,2 @@
+ui_out '{ "jsonrpc": "2.0", "method": "set_ui_options", "params": [{}] }'
+ui_out '{ "jsonrpc": "2.0", "method": "draw", "params": [[[{ "face": { "fg": "black", "bg": "white", "attributes": [] }, "contents": "p" }, { "face": { "fg": "default", "bg": "default", "attributes": [] }, "contents": "rint " }, { "face": { "fg": "red", "bg": "default", "attributes": [] }, "contents": "<< \"\";\u000a" }], [{ "face": { "fg": "red", "bg": "default", "attributes": [] }, "contents": "part of heredoc\u000a" }], [{ "face": { "fg": "default", "bg": "default", "attributes": [] }, "contents": "\u000a" }], [{ "face": { "fg": "default", "bg": "default", "attributes": [] }, "contents": "not part of heredoc\u000a" }]], { "fg": "default", "bg": "default", "attributes": [] }, { "fg": "blue", "bg": "default", "attributes": [] }] }'