added shell tab complete

util/shell_complete.go

@@ -0,0 +1,90 @@
+/*   SHS: Syntactically Homogeneous Shell
+ *   Copyright (C) 2019  Aidan Hahn
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package util
+
+import (
+    "fmt"
+    "io/ioutil"
+    "strings"
+    "gitlab.com/whom/shs/log"
+    "gitlab.com/whom/shs/ast"
+)
+
+// wrap this in a lambda that passes in the vt and ft
+// I suppose it could be more optimal. Fix if it bothers you
+func ShellCompleter(line string, vt ast.VarTable, ft ast.FuncTable) []string {
+    dir, path, tok := getPathBase(line)
+    compSource := []string{}
+
+    if !path {
+        dir = "."
+    } else {
+        line = tok
+    }
+
+    fobjs, err := ioutil.ReadDir(dir)
+    if err != nil {
+        log.Log(log.DEBUG,
+            "couldnt read dir " + dir + ": " + err.Error(),
+            "complete")
+        if path {
+            return nil
+        }
+    } else {
+        for _, f := range fobjs {
+            compSource = append(compSource, f.Name())
+        }
+    }
+
+    if !path {
+        compSource = append(compSource, ast.ListVars(vt)...)
+        compSource = append(compSource, ast.ListFuncs(ft)...)
+    }
+
+    completions := []string{}
+    for _, i := range compSource {
+        if strings.HasPrefix(i, line) {
+            completions = append(completions, i)
+        }
+    }
+
+    return completions
+}
+
+// returns everything up to the last '/'
+// as well as whether or not a / was found
+// and finally the token after the last /
+func getPathBase(in string) (string, bool, string) {
+    if in == "" {
+        return "", false, ""
+    }
+
+    isPath := false
+
+    i := len(in) - 1
+    for i > 0 {
+        if in[i] == '/' {
+            isPath = true
+            break
+        }
+
+        i -= 1
+    }
+
+    return in[:i], isPath, in[i+1:]
+}