diff --git a/tests/test-acid.js b/tests/test-acid.js
new file mode 100644
index 0000000..4ac7f48
--- /dev/null
+++ b/tests/test-acid.js
@@ -0,0 +1,20 @@
+var X = require('./');
+var opts = { cellNF: true,
+  type: 'file',
+  cellHTML: true,
+  cellFormula: true,
+  cellStyles: false,
+  cellDates: false,
+  sheetStubs: false,
+  sheetRows: 0,
+  bookDeps: false,
+  bookSheets: false,
+  bookProps: false,
+  bookFiles: false,
+  bookVBA: false,
+  WTF: false }
+;
+var FILENAME = './test_files/number_format_entities-2.xlsx';
+wb = X.read(X.write(X.readFile(FILENAME,opts), {type:"buffer", bookType:'xlsx'}), {WTF:true, cellNF: true})
+
+X.writeFile(wb,'/tmp/wb3.xlsx');
diff --git a/tests/test-csv.js b/tests/test-csv.js
new file mode 100644
index 0000000..44f862f
--- /dev/null
+++ b/tests/test-csv.js
@@ -0,0 +1,43 @@
+var argv = require('minimist')(process.argv.slice(2));
+
+var XLSX = require('./');
+var fs = require('fs')
+var INFILE = './test_files/pivot_table_test.xlsm';
+var TESTFILE = './test_files/pivot_table_test.xlsm.';
+//var INFILE = './test_files/formula_stress_test.xlsb';
+//var TESTFILE = './test_files/formula_stress_test.xls.';
+var INFILE ='./test_files/apachepoi_Tables.xlsx';
+var TESTFILE='./test_files/apachepoi_Tables.xlsx.';
+var INFILE = './test_files/apachepoi_45540_classic_Footer.xlsx';
+var TESTFILE = './test_files/apachepoi_45540_classic_Footer.xlsx.';
+var SHEET=argv.p || 0;
+
+function stripbom(x) { return x.replace(/^\ufeff/,""); }
+function fixcsv(x) { return stripbom(x).replace(/\t/g,",").replace(/#{255}/g,"").replace(/"/g,"").replace(/[\n\r]+/g,"\n").replace(/\n*$/,""); }
+
+
+wb = XLSX.readFile(INFILE, {cellNF: true});
+
+//XLSX.writeFile(wb, '/tmp/test-csv.xlsx');
+//var wb = XLSX.readFile('/tmp/test-csv.xlsx', {cellNF: true});
+
+wb = XLSX.read(XLSX.write(wb, {type:"buffer", bookType:'xlsx'}), {cellNF: true})
+
+
+var csv = fixcsv(XLSX.utils.make_csv(wb.Sheets[wb.SheetNames[SHEET]]))
+console.log('==================')
+console.log( csv);
+console.log('------------')
+var exp = fixcsv(fs.readFileSync(TESTFILE + SHEET+ '.csv','utf8'))
+console.log(exp)
+console.log('.............')
+console.log(csv==exp);
+
+console.log(csv.length, exp.length)
+if (argv.d) {
+for (var i=0; i<csv.length; i++) {
+  console.log([csv[i], exp[i]], csv[i] ==exp[i]);
+}
+}
+//console.log(wb.Sheets[wb.SheetNames[0]].C2)
+
diff --git a/tests/test-min.js b/tests/test-min.js
new file mode 100644
index 0000000..96ee7f2
--- /dev/null
+++ b/tests/test-min.js
@@ -0,0 +1,10 @@
+var X = require('./xlsx.js');
+var file = 'test_files/2013/apachepoi_44861.xls.xlsb';
+var file = 'test_files/apachepoi_44861.xls';
+var opts = {cellNF: true};
+describe('from 2013', function() {
+		it('should parse', function() {
+			var wb = X.readFile(file, opts);
+		});
+	});
+
diff --git a/tests/test-open.js b/tests/test-open.js
new file mode 100644
index 0000000..9e0e996
--- /dev/null
+++ b/tests/test-open.js
@@ -0,0 +1,8 @@
+var XLSX = require('./');
+
+wbin = XLSX.readFile('/tmp/wb.xlsx', {type: "xlsx"});
+
+XLSX.writeFile(wbin, '/tmp/wb2.xlsx', {
+  defaultCellStyle: { font: { name: "Verdana", sz: 11, color: "FF00FF88"}, fill: {fgColor: {rgb: "FFFFAA00"}}}
+});
+
diff --git a/tests/test-style.js b/tests/test-style.js
new file mode 100644
index 0000000..bb62103
--- /dev/null
+++ b/tests/test-style.js
@@ -0,0 +1,694 @@
+var XLSX = require('../.');
+
+var JSZip = require('jszip');
+var fs = require('fs');
+var cheerio = require('cheerio');
+
+var assert = require('assert');
+
+function JSDateToExcelDate(inDate) {
+  return 25569.0 + ((inDate.getTime() - (inDate.getTimezoneOffset() * 60 * 1000)) / (1000 * 60 * 60 * 24));
+}
+
+var defaultCellStyle = { font: { name: "Verdana", sz: 11, color: "FF00FF88"}, fill: {fgColor: {rgb: "FFFFAA00"}}};
+
+// test to see if everything on the left equals its counterpart on the right
+// but the right hand object may have other attributes which we might not care about
+function basicallyEquals(left, right) {
+  if (Array.isArray(left) && Array.isArray(right)) {
+    for (var i=0; i<left.length; i++) {
+      if (!basicallyEquals(left[i], right[i] )) {
+        return false;
+      }
+    }
+    return true;
+  }
+  else if (typeof left == 'object' && typeof right == 'object') {
+    for (var key in left) {
+      if (key != 'bgColor') {
+        if (!basicallyEquals(left[key], right[key] )) {
+          if (JSON.stringify(left[key])=="{}" && right[key] == undefined) return true;
+          if (JSON.stringify(right[key])=="{}" && left[key] == undefined) return true;
+          return false;
+        }
+      }
+    }
+    return true;
+  }
+  else {
+    if (left != right) {
+      return false;
+    }
+    return true;
+  }
+}
+
+
+describe('styles with blank cells', function () {
+  it ('retains styles with blank cells', function() {
+
+
+    var OUTFILE = '/tmp/ex1.xlsx';
+    var OUTFILE2 = '/tmp/ex1a.xlsx';
+
+    var workbook = {
+      SheetNames : ["Sheet1"],
+      Sheets: {
+        "Sheet1": {
+          "B2": {v: "Top left", s: { border: { top: { style: 'medium', color: { rgb: "FFFFAA00"}}, left: { style: 'medium', color: { rgb: "FFFFAA00"}} }}},
+          "C2": {v: "Top right", s: { border: { top: { style: 'medium', color: { rgb: "FFFFAA00"}}, right: { style: 'medium', color: { rgb: "FFFFAA00"}} }}},
+          "B3": {v: "Bottom left", s: { border: { bottom: { style: 'medium', color: { rgb: "FFFFAA00"}}, left: { style: 'medium', color: { rgb: "FFFFAA00"}} }}},
+          "C3": {v: "", s: { border: { bottom: { style: 'medium', color: { rgb: "FFFFAA00"}}, right: { style: 'medium', color: { rgb: "FFFFAA00"}} }}},
+          "!ref":"B2:C3"
+        }
+      }
+    };
+
+    // write the file and read it back...
+    XLSX.writeFile(workbook, OUTFILE, {bookType: 'xlsx', bookSST: false});
+    var workbook2 = XLSX.readFile(OUTFILE, {cellStyles: true});
+    assert(basicallyEquals(workbook.Sheets, workbook2.Sheets));
+
+    XLSX.writeFile(workbook2, OUTFILE2, {bookType: 'xlsx', bookSST: false});
+    var workbook3 = XLSX.readFile(OUTFILE2, {cellStyles: true});
+    assert(basicallyEquals(workbook.Sheets, workbook3.Sheets))
+  });
+});
+
+describe("Export styles", function () {
+  var workbook, wbout, wbin;
+
+  before(function () {
+    workbook = {
+      "SheetNames": [
+        "Main"
+      ],
+      "Sheets": {
+        "Main": {
+          "!merges": [
+            {
+              "s": {
+                "c": 0,
+                "r": 0
+              },
+              "e": {
+                "c": 2,
+                "r": 0
+              }
+            }
+          ],
+          "A1": {
+            "v": "This is a submerged cell",
+            "s": {
+              "border": {
+                "left": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                },
+                "top": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                },
+                "bottom": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                }
+              }
+            },
+            "t": "s"
+          },
+          "B1": {
+            "v": "Pirate ship",
+            "s": {
+              "border": {
+                "top": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                },
+                "bottom": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                }
+              }
+            },
+            "t": "s"
+          },
+          "C1": {
+            "v": "Sunken treasure",
+            "s": {
+              "border": {
+                "right": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                },
+                "top": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                },
+                "bottom": {
+                  "style": "thick",
+                  "color": {
+                    "auto": 1
+                  }
+                }
+              }
+            },
+            "t": "s"
+          },
+          "A2": {
+            "v": "Blank",
+            "t": "s"
+          },
+          "B2": {
+            "v": "Red",
+            "s": {
+              "fill": {
+                "fgColor": {
+                  "rgb": "FFFF0000"
+                }
+              }
+            },
+            "t": "s"
+          },
+          "C2": {
+            "v": "Green",
+            "s": {
+              "fill": {
+                "fgColor": {
+                  "rgb": "FF00FF00"
+                }
+              }
+            },
+            "t": "s"
+          },
+          "D2": {
+            "v": "Blue",
+            "s": {
+              "fill": {
+                "fgColor": {
+                  "rgb": "FF0000FF"
+                }
+              }
+            },
+            "t": "s"
+          },
+          "E2": {
+            "v": "Theme 5",
+            "s": {
+              "fill": {
+                "fgColor": {
+                  "theme": 5
+                }
+              }
+            },
+            "t": "s"
+          },
+          "F2": {
+            "v": "Theme 5 Tint -0.5",
+            "s": {
+              "fill": {
+                "fgColor": {
+                  "theme": 5,
+                  "tint": -0.5
+                }
+              }
+            },
+            "t": "s"
+          },
+          "A3": {
+            "v": "Default",
+            "t": "s"
+          },
+          "B3": {
+            "v": "Arial",
+            "s": {
+              "font": {
+                "name": "Arial",
+                "sz": 24,
+                "color": {
+                  "theme": "5"
+                }
+              }
+            },
+            "t": "s"
+          },
+          "C3": {
+            "v": "Times New Roman",
+            "s": {
+              "font": {
+                "name": "Times New Roman",
+                bold:true,
+                underline: true,
+                italic: true,
+                strike: true,
+                outline: true,
+                shadow: true,
+                vertAlign: "superscript",
+                "sz": 16,
+                "color": {
+                  "rgb": "FF2222FF"
+                }
+              }
+            },
+            "t": "s"
+          },
+          "D3": {
+            "v": "Courier New",
+            "s": {
+              "font": {
+                "name": "Courier New",
+                "sz": 14
+              }
+            },
+            "t": "s"
+          },
+          "A4": {
+            "v": 0.618033989,
+            "t": "n"
+          },
+          "B4": {
+            "v": 0.618033989,
+            "t": "n"
+          },
+          "C4": {
+            "v": 0.618033989,
+            "t": "n"
+          },
+          "D4": {
+            "v": 0.618033989,
+            "t": "n",
+            "s": {
+              "numFmt": "0.00%"
+            }
+          },
+          "E4": {
+            "v": 0.618033989,
+            "t": "n",
+            "s": {
+              "numFmt": "0.00%",
+              "fill": {
+                "fgColor": {
+                  "rgb": "FFFFCC00"
+                }
+              }
+            }
+          },
+          "A5": {
+            "v": 0.618033989,
+            "t": "n",
+            "s": {
+              "numFmt": "0%"
+            }
+          },
+          "B5": {
+            "v": 0.618033989,
+            "t": "n",
+            "s": {
+              "numFmt": "0.0%"
+            }
+          },
+          "C5": {
+            "v": 0.618033989,
+            "t": "n",
+            "s": {
+              "numFmt": "0.00%"
+            }
+          },
+          "D5": {
+            "v": 0.618033989,
+            "t": "n",
+            "s": {
+              "numFmt": "0.000%"
+            }
+          },
+          "E5": {
+            "v": 0.618033989,
+            "t": "n",
+            "s": {
+              "numFmt": "0.0000%"
+            }
+          },
+          "F5": {
+            "v": 0,
+            "t": "n",
+            "s": {
+              "numFmt": "0.00%;\\(0.00%\\);\\-;@",
+              "fill": {
+                "fgColor": {
+                  "rgb": "FFFFCC00"
+                }
+              }
+            }
+          },
+          "A6": {
+            "v": "Sat Mar 21 2015 23:47:34 GMT-0400 (EDT)",
+            "t": "s"
+          },
+          "B6": {
+            "v": 42084.99137416667,
+            "t": "n"
+          },
+          "C6": {
+            "v": 42084.99137416667,
+            "s": {
+              "numFmt": "d-mmm-yy"
+            },
+            "t": "n"
+          },
+          "A7": {
+            "v": "left",
+            "s": {
+              "alignment": {
+                "horizontal": "left"
+              }
+            },
+            "t": "s"
+          },
+          "B7": {
+            "v": "center",
+            "s": {
+              "alignment": {
+                "horizontal": "center"
+              }
+            },
+            "t": "s"
+          },
+          "C7": {
+            "v": "right",
+            "s": {
+              "alignment": {
+                "horizontal": "right"
+              }
+            },
+            "t": "s"
+          },
+          "A8": {
+            "v": "vertical",
+            "s": {
+              "alignment": {
+                "vertical": "top"
+              }
+            },
+            "t": "s"
+          },
+          "B8": {
+            "v": "vertical",
+            "s": {
+              "alignment": {
+                "vertical": "center"
+              }
+            },
+            "t": "s"
+          },
+          "C8": {
+            "v": "vertical",
+            "s": {
+              "alignment": {
+                "vertical": "bottom"
+              }
+            },
+            "t": "s"
+          },
+          "A9": {
+            "v": "indent",
+            "s": {
+              "alignment": {
+                "indent": "1"
+              }
+            },
+            "t": "s"
+          },
+          "B9": {
+            "v": "indent",
+            "s": {
+              "alignment": {
+                "indent": "2"
+              }
+            },
+            "t": "s"
+          },
+          "C9": {
+            "v": "indent",
+            "s": {
+              "alignment": {
+                "indent": "3"
+              }
+            },
+            "t": "s"
+          },
+          "A10": {
+            "v": "In publishing and graphic design, lorem ipsum is a filler text commonly used to demonstrate the graphic elements of a document or visual presentation. ",
+            "s": {
+              "alignment": {
+                "wrapText": 1,
+                "horizontal": "right",
+                "vertical": "center",
+                "indent": 1
+              }
+            },
+            "t": "s"
+          },
+          "A11": {
+            "v": 41684.35264774306,
+            "s": {
+              "numFmt": "m/d/yy"
+            },
+            "t": "n"
+          },
+          "B11": {
+            "v": 41684.35264774306,
+            "s": {
+              "numFmt": "d-mmm-yy"
+            },
+            "t": "n"
+          },
+          "C11": {
+            "v": 41684.35264774306,
+            "s": {
+              "numFmt": "h:mm:ss AM/PM"
+            },
+            "t": "n"
+          },
+          "D11": {
+            "v": 42084.99137416667,
+            "s": {
+              "numFmt": "m/d/yy"
+            },
+            "t": "n"
+          },
+          "E11": {
+            "v": 42065.02247239584,
+            "s": {
+              "numFmt": "m/d/yy"
+            },
+            "t": "n"
+          },
+          "F11": {
+            "v": 42084.99137416667,
+            "s": {
+              "numFmt": "m/d/yy h:mm:ss AM/PM"
+            },
+            "t": "n"
+          },
+          "A12": {
+            "v": "Apple",
+            "s": {
+              "border": {
+                "top": {
+                  "style": "thin"
+                },
+                "left": {
+                  "style": "thin"
+                },
+                "right": {
+                  "style": "thin"
+                },
+                "bottom": {
+                  "style": "thin"
+                }
+              }
+            },
+            "t": "s"
+          },
+          "C12": {
+            "v": "Apple",
+            "s": {
+              "border": {
+                "diagonalUp": 1,
+                "diagonalDown": 1,
+                "top": {
+                  "style": "dashed",
+                  "color": {
+                    "auto": 1
+                  }
+                },
+                "right": {
+                  "style": "medium",
+                  "color": {
+                    "theme": "5"
+                  }
+                },
+                "bottom": {
+                  "style": "hair",
+                  "color": {
+                    "theme": 5,
+                    "tint": "-0.3"
+                  }
+                },
+                "left": {
+                  "style": "thin",
+                  "color": {
+                    "rgb": "FFFFAA00"
+                  }
+                },
+                "diagonal": {
+                  "style": "dotted",
+                  "color": {
+                    "auto": 1
+                  }
+                }
+              }
+            },
+            "t": "s"
+          },
+          "E12": {
+            "v": "Pear",
+            "s": {
+              "border": {
+                "diagonalUp": 1,
+                "diagonalDown": 1,
+                "top": {
+                  "style": "dashed",
+                  "color": {
+                    "auto": 1
+                  }
+                },
+                "right": {
+                  "style": "dotted",
+                  "color": {
+                    "theme": "5"
+                  }
+                },
+                "bottom": {
+                  "style": "mediumDashed",
+                  "color": {
+                    "theme": 5,
+                    "tint": "-0.3"
+                  }
+                },
+                "left": {
+                  "style": "double",
+                  "color": {
+                    "rgb": "FFFFAA00"
+                  }
+                },
+                "diagonal": {
+                  "style": "hair",
+                  "color": {
+                    "auto": 1
+                  }
+                }
+              }
+            },
+            "t": "s"
+          },
+          "A13": {
+            "v": "Up 90",
+            "s": {
+              "alignment": {
+                "textRotation": 90
+              }
+            },
+            "t": "s"
+          },
+          "B13": {
+            "v": "Up 45",
+            "s": {
+              "alignment": {
+                "textRotation": 45
+              }
+            },
+            "t": "s"
+          },
+          "C13": {
+            "v": "Horizontal",
+            "s": {
+              "alignment": {
+                "textRotation": 0
+              }
+            },
+            "t": "s"
+          },
+          "D13": {
+            "v": "Down 45",
+            "s": {
+              "alignment": {
+                "textRotation": 135
+              }
+            },
+            "t": "s"
+          },
+          "E13": {
+            "v": "Down 90",
+            "s": {
+              "alignment": {
+                "textRotation": 180
+              }
+            },
+            "t": "s"
+          },
+          "F13": {
+            "v": "Vertical",
+            "s": {
+              "alignment": {
+                "textRotation": 255
+              }
+            },
+            "t": "s"
+          },
+          "A14": {
+            "v": "Font color test",
+            "s": {
+              "font": {
+                "color": {
+                  "rgb": "FFC6EFCE"
+                }
+              }
+            },
+            "t": "s"
+          },
+          "!ref": "A1:F14"
+        }
+      }
+    }
+  });
+
+
+  it('can write to a file and read the file back', function () {
+    XLSX.writeFile(workbook, '/tmp/wb.xlsx',  { defaultCellStyle: defaultCellStyle });
+    var wb1 = XLSX.readFile('/tmp/wb.xlsx', {type: "xlsx", cellStyles: true, cellNF: true, WTF:true});
+    assert(basicallyEquals(workbook.Sheets.Main,wb1.Sheets.Main));
+  });
+
+  it('can write to a buffer and read the file back', function () {
+    var wb2 = XLSX.read(XLSX.write(workbook, {type:"buffer", bookType: 'xlsx'}), {cellStyles: true, cellNF: true})
+    XLSX.writeFile(wb2, '/tmp/wb2.xlsx',  { defaultCellStyle: defaultCellStyle });
+    assert(basicallyEquals(workbook.Sheets.Main,wb2.Sheets.Main));
+  });
+
+});
+