fix: num to keep now works with date patterns that are all numbers

Author: Gareth Jones

lib/RollingFileWriteStream.js

@@ -246,8 +246,8 @@ class RollingFileWriteStream extends Writable {
     debug("_clean: existing files are: ", existingFileDetails);
     if (this._tooManyFiles(existingFileDetails.length)) {
       const fileNamesToRemove = existingFileDetails
-        .map(f => path.format({ dir: this.fileObject.dir, base: f.filename }))
-        .slice(0, existingFileDetails.length - this.options.numToKeep - 1);
+        .slice(0, existingFileDetails.length - this.options.numToKeep - 1)
+        .map(f => path.format({ dir: this.fileObject.dir, base: f.filename }));
       await deleteFiles(fileNamesToRemove);
     }
   }

lib/fileNameParser.js

@@ -40,6 +40,10 @@ module.exports = ({ file, keepFileExt, pattern }) => {
     if (indexStr !== undefined && indexStr.match(/^\d+$/)) {
       dateStr = f.slice(0, -1 * (indexStr.length + 1));
       debug(`dateStr is ${dateStr}`);
+      if (pattern && !dateStr) {
+        dateStr = indexStr;
+        indexStr = "0";
+      }
     } else {
       indexStr = "0";
     }

test/fileNameParser-test.js

@@ -100,4 +100,27 @@ describe("fileNameParser", () => {
       });
     });
   });
+
+  describe("with a two-digit date pattern", () => {
+    const parser = require("../lib/fileNameParser")({
+      file: {
+        dir: "/path/to/file",
+        base: "thing.log",
+        ext: ".log",
+        name: "thing"
+      },
+      pattern: "mm"
+    });
+    it("should take a filename and return the date", () => {
+      const expectedTimestamp = new Date(0,0);
+      expectedTimestamp.setMinutes(34);
+      parser("thing.log.34").should.eql({
+        filename: "thing.log.34",
+        date: "34",
+        isCompressed: false,
+        index: 0,
+        timestamp: expectedTimestamp.getTime()
+      });
+    });
+  })
 });