Use virtual lines to show output v1 SUPERSEDED

Andrey Popp: 1
 Use virtual lines to show output

 1 files changed, 28 insertions(+), 37 deletions(-)

[PATCH] Use virtual lines to show output Export this patch

Neovim 0.6.0 was recently released and has added a new feature called
virtual lines. This allows to attach a set of "out-of-buffer" lines to
some locations via extmark mechanism.

This patch changes how output is shown - instead of making a separate
split buffer it shows computed value as a set of virtual lines attached
to the "end" of the computed region.

See https://twitter.com/andreypopp/status/1466543075925188612 for the example of
how it looks.

Thanks for the plugin!
---
 lua/bqn.lua | 65 +++++++++++++++++++++++------------------------------
 1 file changed, 28 insertions(+), 37 deletions(-)

diff --git a/lua/bqn.lua b/lua/bqn.lua
index de733b3..2004940 100644
--- a/lua/bqn.lua
+++ b/lua/bqn.lua
@@ -1,36 +1,17 @@
-local buf = nil
-local win = nil
+local ns = vim.api.nvim_create_namespace('bqn-out')
 
-local function check_buf()
-    if win == nil or not vim.api.nvim_win_is_valid(win) then
-        local prev = vim.api.nvim_get_current_win()
-        if buf == nil then
-            buf = vim.api.nvim_create_buf(false, false)
-        end
-        vim.api.nvim_buf_set_name(buf, "BQN")
-        vim.api.nvim_buf_set_option(buf, "buftype", "nofile")
-        vim.api.nvim_buf_set_option(buf, "swapfile", false)
-        vim.api.nvim_buf_set_option(buf, "modeline", false)
-        vim.cmd("below 3split")
-        vim.api.nvim_win_set_buf(vim.api.nvim_get_current_win(), buf)
-        win = vim.api.nvim_get_current_win()
-        vim.api.nvim_win_set_option(win, "wrap", false)
-        vim.api.nvim_set_current_win(prev)
-    elseif vim.api.nvim_win_is_valid(win) then
-        local winid = vim.api.nvim_eval("bufwinid(" .. buf .. ")")
-        if winid == -1 then
-            local prev = vim.api.nvim_get_current_win()
-            vim.cmd("below 3split")
-            vim.api.nvim_win_set_buf(vim.api.nvim_get_current_win(), buf)
-            win = vim.api.nvim_get_current_win()
-            vim.api.nvim_set_current_win(prev)
-        end
+function evalBQN(from, to, pretty)
+    while to > 0 do
+      local line = vim.api.nvim_buf_get_lines(0, to - 1, to, true)[1]
+      if #line ~= 0 then break end
+      to = to - 1
     end
-end
 
-function evalBQN(from, to, pretty)
-    local code = vim.api.nvim_buf_get_lines(0, from - 1, to, true)
+    if from > to then
+      from = to
+    end
 
+    local code = vim.api.nvim_buf_get_lines(0, 0, to, true)
     local program = ""
     for k, v in ipairs(code) do
         program = program .. v .. "\n"
@@ -50,22 +31,32 @@ function evalBQN(from, to, pretty)
         bqn = "BQN"
     end
 
-    local executable = assert(io.popen(bqn .. " -" .. flag .. " \"" .. program .. "\""))
+    local cmd = bqn .. " -" .. flag .. " \"" .. program .. "\""
+    local executable = assert(io.popen(cmd))
     local output = executable:read('*all')
-    executable:close()
-
-    check_buf()
 
     local lines = {}
     local line_count = 0
     for line in output:gmatch("[^\n]+") do
-        table.insert(lines, line)
+        table.insert(lines, {{' ' .. line, 'Comment'}})
         line_count = line_count + 1
     end
+        table.insert(lines, {{' ', 'Comment'}})
+
+    local total_lines = vim.api.nvim_buf_line_count(0)
+    local cto = to + 1
+    while cto <= total_lines do
+      local line = vim.api.nvim_buf_get_lines(0, cto-1, cto, true)[1]
+      if #line ~= 0 then break end
+      cto = cto + 1
+    end
 
-    vim.api.nvim_buf_set_lines(buf, -1, -1, false, lines)
-    vim.api.nvim_win_set_height(win, line_count)
-    vim.api.nvim_win_set_cursor(win, {vim.api.nvim_buf_line_count(buf), 0})
+    vim.api.nvim_buf_clear_namespace(0, ns, from - 1, cto - 1)
+    vim.api.nvim_buf_set_extmark(0, ns, to - 1, 0, {
+      end_line = to - 1,
+      end_col = 3,
+      virt_lines=lines
+    })
 end
 
 return {
-- 
2.30.2