Basic non-compliant autocompletion via LSP

internal/buffer/autocomplete.go

@@ -7,6 +7,7 @@ import (
 	"sort"
 	"strings"
 
+	lspt "github.com/sourcegraph/go-lsp"
 	"github.com/zyedidia/micro/v2/internal/util"
 )
 
@@ -203,3 +204,34 @@ func BufferComplete(b *Buffer) ([]string, []string) {
 
 	return completions, suggestions
 }
+
+func LSPComplete(b *Buffer) ([]string, []string) {
+	c := b.GetActiveCursor()
+	_, argstart := GetWord(b)
+
+	if argstart == -1 {
+		return []string{}, []string{}
+	}
+
+	pos := lspt.Position{
+		Line:      c.Y,
+		Character: c.X,
+	}
+	items, err := b.server.Completion(b.AbsPath, pos)
+	if err != nil {
+		return []string{}, []string{}
+	}
+
+	suggestions := make([]string, len(items))
+
+	for i, item := range items {
+		suggestions[i] = item.Label
+	}
+
+	completions := make([]string, len(suggestions))
+	for i := range suggestions {
+		completions[i] = util.SliceEndStr(suggestions[i], c.X-argstart)
+	}
+
+	return completions, suggestions
+}

internal/buffer/buffer.go

@@ -138,7 +138,9 @@ func (b *SharedBuffer) insert(pos Loc, value []byte) {
 	inslines := bytes.Count(value, []byte{'\n'})
 	b.MarkModified(pos.Y, pos.Y+inslines)
 
-	b.lspDidChange(pos, pos.MoveLA(util.CharacterCount(value), b.LineArray), string(value))
+	p := pos
+	p.X += util.CharacterCount(value)
+	b.lspDidChange(pos, p, string(value))
 }
 func (b *SharedBuffer) remove(start, end Loc) []byte {
 	b.isModified = true
@@ -405,7 +407,11 @@ func NewBuffer(r io.Reader, size int64, path string, startcursor Loc, btype BufT
 			if ok && l.Installed() {
 				b.server, _ = lsp.StartServer(l)
 				b.server.Initialize(gopath.Dir(b.AbsPath))
-				b.server.DidOpen(b.AbsPath, ft, string(b.Bytes()), b.version)
+				bytes := b.Bytes()
+				if len(bytes) == 0 {
+					bytes = []byte{'\n'}
+				}
+				b.server.DidOpen(b.AbsPath, ft, string(bytes), b.version)
 			}
 		}
 	}