Add a Go script, containing highlighters and auto-indent functions

rc/golang.kak

@@ -0,0 +1,77 @@
+# https://golang.org/
+#
+
+# Detection
+# ‾‾‾‾‾‾‾‾‾
+
+hook global BufCreate .*[.](go) %{
+    set buffer filetype golang
+}
+
+# Highlighters
+# ‾‾‾‾‾‾‾‾‾‾‾‾
+
+addhl -group / regions -default code golang \
+    back_string '`' '`' '' \
+    double_string '"' (?<!\\)(\\\\)*" '' \
+    single_string "'" (?<!\\)(\\\\)*' '' \
+    comment '//' $ ''
+
+addhl -group /golang/back_string fill string
+addhl -group /golang/double_string fill string
+addhl -group /golang/single_string fill string
+addhl -group /golang/comment fill comment
+
+addhl -group /golang/code regex %{\<(false|true|nil)\>|\<-?(0x[0-9a-zA-Z]+|\d+)\>} 0:value
+addhl -group /golang/code regex \<(break|default|defer|else|fallthrough|for|func|go|goto|if|import|interface|make|new|package|range|return|select|case|switch|type|continue)\> 0:keyword
+addhl -group /golang/code regex \<(bool|byte|chan|complex128|complex64|float32|float64|int|int16|int32|int64|int8|interface|intptr|map|rune|string|struct|uint|uint16|uint32|uint64|uint8)\> 0:type
+addhl -group /golang/code regex \<(const)\> 0:attribute
+
+# Commands
+# ‾‾‾‾‾‾‾‾
+
+def -hidden _golang-indent-on-new-line %~
+    eval -draft -itersel %=
+        # preserve previous line indent
+        try %{ exec -draft \;K<a-&> }
+        # indent after lines ending with { or (
+        try %[ exec -draft k<a-x> <a-k> [{(]\h*$ <ret> j<a-gt> ]
+        # cleanup trailing white spaces on the previous line
+        try %{ exec -draft k<a-x> s \h+$ <ret>d }
+        # align to opening paren of previous line
+        try %{ exec -draft [( <a-k> \`\([^\n]+\n[^\n]*\n?\' <ret> s \`\(\h*.|.\' <ret> '<a-;>' & }
+        # copy // comments prefix
+        try %{ exec -draft \;<c-s>k<a-x> s ^\h*\K/{2,} <ret> y<c-o><c-o>P<esc> }
+        # indent after a switch's case/default statements
+        try %[ exec -draft k<a-x> <a-k> ^\h*(case|default).*:$ <ret> j<a-gt> ]
+        # indent after if|else|while|for
+        try %[ exec -draft \;<a-F>)MB <a-k> \`(if|else|while|for)\h*\(.*\)\h*\n\h*\n?\' <ret> s \`|.\' <ret> 1<a-&>1<a-space><a-gt> ]
+    =
+~
+
+def -hidden _golang-indent-on-opening-curly-brace %[
+    # align indent with opening paren when { is entered on a new line after the closing paren
+    try %[ exec -draft -itersel h<a-F>)M <a-k> \`\(.*\)\h*\n\h*\{\' <ret> s \`|.\' <ret> 1<a-&> ]
+]
+
+def -hidden _golang-indent-on-closing-curly-brace %[
+    # align to opening curly brace when alone on a line
+    try %[ exec -itersel -draft <a-h><a-k>^\h+\}$<ret>hms\`|.\'<ret>1<a-&> ]
+]
+
+# Initialization
+# ‾‾‾‾‾‾‾‾‾‾‾‾‾‾
+
+hook global WinSetOption filetype=golang %{
+    addhl ref golang
+
+    # cleanup trailing whitespaces when exiting insert mode
+    hook window InsertEnd .* -group golang-hooks %{ try %{ exec -draft <a-x>s^\h+$<ret>d } }
+    hook window InsertChar \n -group golang-indent _golang-indent-on-new-line
+    hook window InsertChar \{ -group golang-indent _golang-indent-on-opening-curly-brace
+    hook window InsertChar \} -group golang-indent _golang-indent-on-closing-curly-brace
+}
+
+hook global WinSetOption filetype=(?!golang).* %{
+    rmhl golang
+}