Added tests for formula evaluation

* Minor fixes as detected by the tests

autoload/tablemode/spreadsheet.vim

@@ -233,7 +233,7 @@ endfunction
 " tablemode#spreadsheet#GetCells(row) - Get values of all cells in a row as a List.
 " tablemode#spreadsheet#GetCells(0, col) - Get values of all cells in a column as a List.
 " tablemode#spreadsheet#GetCells(row, col) - Get the value of table cell by given row, col.
-function! tablemode#spreadsheet#GetCells(line, ...) abort "{{{2
+function! tablemode#spreadsheet#GetCells(line, ...) abort
   let line = tablemode#utils#line(a:line)
 
   if tablemode#table#IsATableRow(line)
@@ -281,12 +281,12 @@ endfunction
 
 function! tablemode#spreadsheet#GetCell(...) "{{{2
   if a:0 == 0
-    let [row, colm] = [tablemode#RowNr('.'), tablemode#spreadsheet#ColumnNr('.')]
+    let [row, colm] = [tablemode#spreadsheet#RowNr('.'), tablemode#spreadsheet#ColumnNr('.')]
   elseif a:0 == 2
     let [row, colm] = [a:1, a:2]
   endif
 
-  return tablemode#spreadsheet#GetCells('.', row, col)
+  return tablemode#spreadsheet#GetCells('.', row, colm)
 endfunction
 
 function! tablemode#spreadsheet#GetRow(row, ...) abort "{{{2
@@ -418,8 +418,8 @@ function! tablemode#spreadsheet#Average(range, ...) abort "{{{2
   return s:Average(call('tablemode#spreadsheet#GetCellRange', args))
 endfunction
 
-function! tablemode#spreadsheet#AddFormula() "{{{2
+function! tablemode#spreadsheet#AddFormula(...) "{{{2
-  let fr = input('f=')
+  let fr = a:0 ? a:1 : input('f=')
   let row = tablemode#spreadsheet#RowNr('.')
   let colm = tablemode#spreadsheet#ColumnNr('.')
   let indent = indent('.')

t/fixtures/formula/formula.txt

@@ -0,0 +1,7 @@
+| Item     | Cost  |
+|----------+-------|
+| Bread    |    20 |
+| Tomatoes |     5 |
+| Pasta    |   100 |
+| Total    |     0 |
+/* tmf: $5,2=Sum(1:-1) */

t/fixtures/formula/sample.txt

@@ -0,0 +1,7 @@
+| Item     | Cost |
+|----------+------|
+| Bread    |   20 |
+| Tomatoes |    5 |
+| Pasta    |  100 |
+| Total    |      |
+| Test     |      |

t/spreadsheet.vim

@@ -93,4 +93,41 @@ describe 'spreadsheet'
       call tablemode#spreadsheet#DeleteColumn()
       Expect tablemode#spreadsheet#ColumnCount('.') == 1
     end
+  end
+
+  describe 'Formulas'
+    describe 'Add Formula'
+      before
+        new
+        read t/fixtures/formula/sample.txt
+      end
+
+      it 'should add a formula successfully'
+        call cursor(6, 15)
+        call tablemode#spreadsheet#AddFormula("Sum(1:4)")
+        Expect tablemode#spreadsheet#GetCell() == '125.0'
+        call cursor(8, 15)
+        Expect getline('.') == '/* tmf: $5,2=Sum(1:4) */'
+
+        call cursor(7, 15)
+        call tablemode#spreadsheet#AddFormula("Sum(1:-1)")
+        Expect tablemode#spreadsheet#GetCell() == '250.0'
+        call cursor(8, 15)
+        Expect getline('.') == '/* tmf: $5,2=Sum(1:4) ; $6,2=Sum(1:-1) */'
+      end
+    end
+
+    describe 'Evaluate Formula'
+      before
+        new
+        read t/fixtures/formula/formula.txt
+      end
+
+      it 'should evaluate the formula successfull'
+        call cursor(6, 15)
+        call tablemode#spreadsheet#EvaluateFormulaLine()
+        Expect &modified == 1
+        Expect tablemode#spreadsheet#GetCell() == '125.0'
+      end
+    end
   end