Add function to search for next link on line

By choosing 'line' in the `zettel_link_following` option, the link to be
opened will be searched for on the complete rest of the line, meaning
from the cursor to the newline symbol onwards.

README.md

@@ -5,9 +5,9 @@ To develop / debug:
 start neovim with  `nvim --cmd "set rtp+=$(pwd)" .` to automatically load the files in project dir as if they were on path
 
 next up:
-* link following option (under cursor, next on line)
-* next link on line function (actions)
-* helper function to decide which one to use from A.open
+* [x] link following option (under cursor, next on line)
+* [x] next link on line function (actions)
+* [x] helper function to decide which one to use from A.open
 
 ## TODO: needed functionality
 
@@ -19,10 +19,11 @@ next up:
   * [ ] list anchors
   * [ ] list filenames
 * [ ] link following (to existing anchor)
+  * [ ] fallback to filename if anchor invalid / not found
 * [ ] link creation (to existing note)
   * [ ] list existing
   * [ ] create link (md / wiki)
-* [ ] link switching (to another existing note)
+* [ ] link switching (point to another existing note)
 * [ ] note search (title / full-text)
 * [ ] jump to zettel (open existing anchor)
   * [ ] select by anchor
@@ -32,13 +33,14 @@ next up:
  * [x] zettel extension
  * [x] link style (wiki/markdown)
   * [ ] custom link style?
- * [ ] link detection/following (under word, next on line)
+ * [x] link detection/following (under word, next on line)
  * [ ] recursive dir lookup for zettel
  * [ ] zettel anchor regex
 
 ## TODO: nice-to-haves
 
 * [ ] refactor parsers (md/wiki) to be tables of functions/regex in options, so e.g. valid link detection can call `options.parser.isValidLink(link)` or transformation `options.parser.styleLink(anchor, text)`
+  * [ ] enable custom parser supply
 * [ ] completion engine (e.g. for `completion-nvim`, look in completion_buffers/completion-tags for reference)
 * [ ] zettel caching for big directories
 * [ ] backlinks (via rg for filename anchor?)

lua/zettelkasten/action.lua

@@ -1,5 +1,9 @@
 local A = {}
 
+local o = require 'zettelkasten.options'
+
+local parsers = {markdown = "%[.-%]%((.-)%)", wiki = "%[%[(.+)|?.-%]%]"}
+
 -- Extracts a file name from a link and opens the corresponding file
 -- in the current buffer.
 -- Takes an optional input parameter
@@ -12,15 +16,24 @@ end
 
 -- Gets the input at the current buffer cursor and opens it
 -- in the current buffer.
-function A.open_selected()
-    -- TODO decide between currentword/restofline option
-    A.open(A.get_link_under_cursor())
+-- Takes an optional style of link following to use,
+-- superseding the one set in options.
+function A.open_selected(style)
+    local style = style or o.zettel().link_following
+    if style == 'line' then
+        A.open(A.get_next_link_on_line())
+    elseif style == 'cursor' then
+        A.open(A.get_link_under_cursor())
+    end
 end
 
--- Return only the link reference portion of a markdown/wiki style link
+-- Return only the link reference portion of a markdown/wiki style link.
+-- For example, for a markdown link [my text](my-link.md)
+-- it would only return my-link.md
 function A.extract_link(input)
     if not input then return end
-    return input:match("%[%[(.+)|?.*%]%]") or input:match("%[.*%]%((.+)%)")
+    for _, parser in pairs(parsers) do return input:match(parser) end
+    return
 end
 
 -- Returns the word currently under cursor, the vim equivalent of yiW.
@@ -33,48 +46,10 @@ function A.get_link_under_cursor(small)
     return word
 end
 
--- -- Returns the content of the line from the cursor onwards.
--- function A.get_next_link_on_line()
---     local line = vim.api.nvim_get_current_line()
---     local linenr = vim.api.nvim_win_get_cursor(0)[1]
---     print(line, linenr)
---     return ""
--- end
+-- Returns the content of the line from the cursor onwards.
+function A.get_next_link_on_line()
+    local line = vim.api.nvim_get_current_line()
+    return line:sub(vim.api.nvim_win_get_cursor(0)[2])
+end
 
 return {open = A.open, open_selected = A.open_selected}
-
--- local function get_selection()
---     s_start = vim.fn.line("'<") - 1
---     s_end = vim.fn.line("'>")
---     return vim.api.nvim_buf_get_lines(0, s_start, s_end, true)
--- end
-
--- -- UGLY HACKS ABOUND
--- function ZK.create_zettel()
---     -- get line and its number
---     local selection
---     local line = vim.api.nvim_get_current_line()
---     local linenr = vim.api.nvim_win_get_cursor(0)[1]
-
---     -- get words under cursor / selected
---     local mode = vim.api.nvim_get_mode()['mode']
---     if mode == "n" then
---         print(vim.fn.line("'<'") - 1)
---         selection = vim.fn.expand("<cWORD>")
---         -- NOT WORKING YET
---     elseif mode == "v" then
---         selection = get_selection()
---     else
---         return
---     end
-
---     -- get valid link
---     local link = l.create(nil, selection)
-
---     -- create new line with selection replaced in middle
---     local st, en = line:find(selection, 0, true)
---     local repl_line = line:sub(1, st - 1) .. link .. line:sub(en + 1)
-
---     -- replace existing line in favor of new one
---     vim.api.nvim_buf_set_lines(0, linenr - 1, linenr, true, {repl_line})
--- end

lua/zettelkasten/action_spec.lua

@@ -11,22 +11,54 @@ describe("open", function()
         assert.spy(vim.api.nvim_command).was_called_with(
             "edit 1910271456_link-to-my-file.md")
     end)
-    it("should not fail when no input is available", function()
+    it("should do nothing when no link passed in", function()
         vim.fn = {expand = function() end}
         assert.is_not_error(action.open)
     end)
 end)
+
 describe("open_selected", function()
-    it("should open the next link found if no argument passed in", function()
-        vim.api = {nvim_command = mock(function() end)}
+    before_each(function()
+        vim.api = {
+            nvim_command = mock(function() end),
+            nvim_get_current_line = function(sure)
+                return
+                    "Hello, this is a line and [mylink](1910271456_link-to-my-file.md) whereas another [link](2030101158 another-link-now.md)"
+            end,
+            nvim_win_get_cursor = function(winnum) return {0, 0} end
+        }
+    end)
+    it("should use the style passed to it, above the one set in options",
+       function()
+        vim.g['zettel_link_following'] = 'cursor'
+
+        vim.api.nvim_get_current_line = mock(vim.api.nvim_get_current_line)
+        action.open_selected("line")
+
+        assert.spy(vim.api.nvim_get_current_line).was_called()
+    end)
+    it("should open link under cursor if option set", function()
+        vim.g['zettel_link_following'] = 'cursor'
         vim.fn = {
             expand = function(sure)
                 return "[" .. sure .. "](1910271456_link-to-my-file.md)"
             end
         }
-
         action.open_selected()
         assert.spy(vim.api.nvim_command).was_called_with(
             "edit 1910271456_link-to-my-file.md")
     end)
+    it("should open next link on line if option set", function()
+        vim.g['zettel_link_following'] = 'line'
+        action.open_selected()
+        assert.spy(vim.api.nvim_command).was_called_with(
+            "edit 1910271456_link-to-my-file.md")
+    end)
+    it("should ignore links before cursor position", function()
+        vim.g['zettel_link_following'] = 'line'
+        vim.api.nvim_win_get_cursor = function(winnum) return {0, 65} end
+        action.open_selected()
+        assert.spy(vim.api.nvim_command).was_called_with(
+            "edit 2030101158 another-link-now.md")
+    end)
 end)