From a4f22c3aadcf0ea13d97e5107b04914935e34cf6 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sat, 26 Jul 2014 17:00:13 -0400
Subject: [PATCH 01/22] Stacktrace.parse() returns multiple results now.

---
 lib/main.coffee | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/main.coffee b/lib/main.coffee
index c0ae98d..0e014f4 100644
--- a/lib/main.coffee
+++ b/lib/main.coffee
@@ -11,9 +11,9 @@ module.exports =
     StacktraceView.registerIn(atom.workspace)
 
     atom.on 'stacktrace:accept-trace', ({trace}) =>
-      t = Stacktrace.parse(trace)
-      t.register()
-      atom.workspace.open t.getUrl()
+      for trace in Stacktrace.parse(trace)
+        trace.register()
+        atom.workspace.open trace.getUrl()
 
   deactivate: ->
     atom.off 'stacktrace:accept-trace'

From 45b85067f02231b9d6833dd03c226f64c93b34ab Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sat, 26 Jul 2014 17:11:35 -0400
Subject: [PATCH 02/22] Spec for rendering the error message.

---
 lib/stacktrace-view.coffee       | 2 +-
 spec/stacktrace-view-spec.coffee | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index 502a184..8bd7617 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -6,7 +6,7 @@ class StacktraceView extends View
   @content: (trace) ->
     @div class: 'stacktrace tool-panel padded', =>
       @div class: 'header panel', =>
-        @h2 trace.message
+        @h2 class: 'error-message', trace.message
       @div class: 'frames', =>
         for frame in trace.frames
           @subview 'frame', new FrameView(frame)
diff --git a/spec/stacktrace-view-spec.coffee b/spec/stacktrace-view-spec.coffee
index df48b26..7a46db0 100644
--- a/spec/stacktrace-view-spec.coffee
+++ b/spec/stacktrace-view-spec.coffee
@@ -29,7 +29,10 @@ describe 'StacktraceView', ->
     trace.register()
     expect(opener(trace.getUrl()).trace).toBe(trace)
 
-  it 'shows the error message'
+  it 'shows the error message', ->
+    text = view.find('.error-message').text()
+    expect(text).toEqual('Boom')
+
   it 'renders a subview for each frame'
 
 describe 'FrameView', ->

From e250a0b3a9961cbf7bd66c45dd46a7b636f23af8 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sat, 26 Jul 2014 17:12:46 -0400
Subject: [PATCH 03/22] Rendering a subview for each Frame.

---
 spec/stacktrace-view-spec.coffee | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/spec/stacktrace-view-spec.coffee b/spec/stacktrace-view-spec.coffee
index 7a46db0..8b1933b 100644
--- a/spec/stacktrace-view-spec.coffee
+++ b/spec/stacktrace-view-spec.coffee
@@ -33,7 +33,9 @@ describe 'StacktraceView', ->
     text = view.find('.error-message').text()
     expect(text).toEqual('Boom')
 
-  it 'renders a subview for each frame'
+  it 'renders a subview for each frame', ->
+    vs = view.find('.frame')
+    expect(vs.length).toBe(3)
 
 describe 'FrameView', ->
   [view] = []

From 3e1c1f7a0b24454e45efc989d066f3ad6ffea7ee Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sat, 26 Jul 2014 17:19:37 -0400
Subject: [PATCH 04/22] Specs for FrameView.

---
 spec/stacktrace-view-spec.coffee | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/spec/stacktrace-view-spec.coffee b/spec/stacktrace-view-spec.coffee
index 8b1933b..e726f4f 100644
--- a/spec/stacktrace-view-spec.coffee
+++ b/spec/stacktrace-view-spec.coffee
@@ -2,7 +2,7 @@
 {Stacktrace, Frame} = require '../lib/stacktrace'
 
 frames = [
-  new Frame('raw0', 'bottom.rb', 12, 'botfunc', 'Boom')
+  new Frame('raw0', 'bottom.rb', 12, 'botfunc')
   new Frame('raw1', 'middle.rb', 42, 'midfunc')
   new Frame('raw2', 'top.rb', 37, 'topfunc')
 ]
@@ -43,6 +43,11 @@ describe 'FrameView', ->
   beforeEach ->
     view = new FrameView(frames[1])
 
-  it 'shows the filename'
-  it 'shows the line number'
-  it 'shows the function name'
+  it 'shows the filename and line number', ->
+    text = view.find('.source-location').text()
+    expect(text).toMatch(/middle\.rb/)
+    expect(text).toMatch(/42/)
+
+  it 'shows the function name', ->
+    text = view.find('.function-name').text()
+    expect(text).toEqual('midfunc')

From 2387c860bb4ae854273f1c23d5263b020e1b83e6 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sat, 26 Jul 2014 17:46:02 -0400
Subject: [PATCH 05/22] Stub out controls for activation and deactivation.

---
 lib/stacktrace-view.coffee  | 13 ++++++++++---
 lib/stacktrace.coffee       |  8 +++++++-
 stylesheets/stacktrace.less | 17 +++++++++++++++++
 3 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index 8bd7617..c4c09bc 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -4,9 +4,16 @@
 class StacktraceView extends View
 
   @content: (trace) ->
-    @div class: 'stacktrace tool-panel padded', =>
-      @div class: 'header panel', =>
+    tclass = if trace.isActive() then 'activated' else 'deactivated'
+    @div class: "stacktrace tool-panel padded #{tclass}", =>
+      @div class: 'panel padded', =>
         @h2 class: 'error-message', trace.message
+        @p class: 'activate-control', =>
+          @button class: 'btn btn-primary selected inline-block', click: 'activate', 'Activate'
+          @span class: 'inline-block', 'to navigate around this stacktrace.'
+        @p class: 'deactivate-control', =>
+          @button class: 'btn btn-primary inline-block', 'Deactivate'
+          @span class: 'inline-block', 'to close the stacktrace navigation panel.'
       @div class: 'frames', =>
         for frame in trace.frames
           @subview 'frame', new FrameView(frame)
@@ -32,7 +39,7 @@ class FrameView extends View
       @div class: 'panel-heading', =>
         @span class: 'function-name text-highlight inline-block', frame.functionName
         @span class: 'source-location text-info inline-block pull-right', =>
-          @text "#{frame.path} @ #{frame.lineNumber}"
+          @text "#{frame.rawPath} @ #{frame.lineNumber}"
       @div class: 'panel-body padded', =>
         @pre output: 'source', 'Source goes here'
 
diff --git a/lib/stacktrace.coffee b/lib/stacktrace.coffee
index cfa23fe..0895f7c 100644
--- a/lib/stacktrace.coffee
+++ b/lib/stacktrace.coffee
@@ -23,6 +23,11 @@ class Stacktrace
   #
   getUrl: -> @url ?= "#{PREFIX}/#{@getChecksum()}"
 
+  # Public: Determine whether or not this Stacktrace is the "active" one. The active Stacktrace is
+  # shown in a bottom navigation panel and highlighted in opened editors.
+  #
+  isActive: -> false
+
   # Internal: Register this trace in a global map by its URL.
   #
   register: ->
@@ -55,7 +60,8 @@ class Stacktrace
 #
 class Frame
 
-  constructor: (@rawLine, @path, @lineNumber, @functionName) ->
+  constructor: (@rawLine, @rawPath, @lineNumber, @functionName) ->
+    @realPath = @rawPath
 
 module.exports =
   PREFIX: PREFIX
diff --git a/stylesheets/stacktrace.less b/stylesheets/stacktrace.less
index 5bf0e72..12721f1 100644
--- a/stylesheets/stacktrace.less
+++ b/stylesheets/stacktrace.less
@@ -8,4 +8,21 @@
   &.enter-dialog .editor {
     height: 300px;
   }
+
+  .frame .panel-heading {
+    font-size: 130%;
+
+    .source-location:hover {
+      cursor: pointer;
+      text-decoration: underline;
+    }
+  }
+
+  &.activated {
+    .activate-control { display: none; }
+  }
+
+  &.deactivated {
+    .deactivate-control { display: none; }
+  }
 }

From f62810c34410bfcc99a685512f81b7b5a0579613 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sat, 26 Jul 2014 18:00:16 -0400
Subject: [PATCH 06/22] Toggle each FrameView.

---
 lib/stacktrace-view.coffee  | 31 ++++++++++++++++++++++++++++---
 stylesheets/stacktrace.less | 13 +++++++++++++
 2 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index c4c09bc..85edb1d 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -12,7 +12,7 @@ class StacktraceView extends View
           @button class: 'btn btn-primary selected inline-block', click: 'activate', 'Activate'
           @span class: 'inline-block', 'to navigate around this stacktrace.'
         @p class: 'deactivate-control', =>
-          @button class: 'btn btn-primary inline-block', 'Deactivate'
+          @button class: 'btn btn-primary inline-block', click: 'deactivate', 'Deactivate'
           @span class: 'inline-block', 'to close the stacktrace navigation panel.'
       @div class: 'frames', =>
         for frame in trace.frames
@@ -21,11 +21,23 @@ class StacktraceView extends View
   initialize: (@trace) ->
 
   # Internal: Return the window title.
+  #
   getTitle: ->
     @trace.message
 
+  # Public: Activate the current {Stacktrace}.
+  #
+  activate: ->
+    console.log 'Activate'
+
+  # Public: Deactivate the current {Stacktrace}.
+  #
+  deactivate: ->
+    console.log 'Deactivate'
+
   # Internal: Register an opener function in the workspace to handle URLs
   # generated by a Stacktrace.
+  #
   @registerIn: (workspace) ->
     workspace.registerOpener (filePath) ->
       trace = Stacktrace.forUrl(filePath)
@@ -37,14 +49,27 @@ class FrameView extends View
   @content: (frame) ->
     @div class: 'frame inset-panel', =>
       @div class: 'panel-heading', =>
+        @span class: 'icon icon-fold inline-block', click: 'minimize'
+        @span class: 'icon icon-unfold inline-block', click: 'restore'
         @span class: 'function-name text-highlight inline-block', frame.functionName
-        @span class: 'source-location text-info inline-block pull-right', =>
+        @span class: 'source-location text-info inline-block pull-right', click: 'navigate', =>
           @text "#{frame.rawPath} @ #{frame.lineNumber}"
-      @div class: 'panel-body padded', =>
+      @div class: 'panel-body padded', outlet: 'body', =>
         @pre output: 'source', 'Source goes here'
 
   initialize: (@frame) ->
 
+  navigate: ->
+    console.log "Navigate"
+
+  minimize: ->
+    @addClass 'minimized'
+    @body.hide 'fast'
+
+  restore: ->
+    @removeClass 'minimized'
+    @body.show 'fast'
+
 module.exports =
   StacktraceView: StacktraceView
   FrameView: FrameView
diff --git a/stylesheets/stacktrace.less b/stylesheets/stacktrace.less
index 12721f1..5fb9d0c 100644
--- a/stylesheets/stacktrace.less
+++ b/stylesheets/stacktrace.less
@@ -18,6 +18,19 @@
     }
   }
 
+  .frame {
+    .icon-fold, .icon-unfold {
+      cursor: pointer;
+    }
+
+    .icon-unfold { display: none; }
+
+    &.minimized {
+      .icon-unfold { display: inline-block; }
+      .icon-fold { display: none; }
+    }
+  }
+
   &.activated {
     .activate-control { display: none; }
   }

From 29586396f18a506188d9f0158ba712afab5dd43a Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sat, 26 Jul 2014 20:36:05 -0400
Subject: [PATCH 07/22] Oops, broke that test when I renamed path.

---
 spec/stacktrace-spec.coffee | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spec/stacktrace-spec.coffee b/spec/stacktrace-spec.coffee
index 889de8c..32590af 100644
--- a/spec/stacktrace-spec.coffee
+++ b/spec/stacktrace-spec.coffee
@@ -26,7 +26,7 @@ describe 'Stacktrace', ->
         expect(trace.message).toBe('whoops (RuntimeError)')
 
       it 'parses file paths from each frame', ->
-        filePaths = (frame.path for frame in trace.frames)
+        filePaths = (frame.realPath for frame in trace.frames)
         expected = [
           '/home/smash/samples/tracer/otherdir/file2.rb'
           '/home/smash/samples/tracer/dir/file1.rb'

From 8aadb50a1388d30e770f319385f3b73ccc761a8e Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 08:34:39 -0400
Subject: [PATCH 08/22] Test case for fetching line context.

---
 lib/stacktrace-view.coffee  |  2 +-
 spec/fixtures/context.txt   | 11 +++++++++++
 spec/stacktrace-spec.coffee | 25 ++++++++++++++++++++++++-
 3 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 spec/fixtures/context.txt

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index 85edb1d..83da43e 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -55,7 +55,7 @@ class FrameView extends View
         @span class: 'source-location text-info inline-block pull-right', click: 'navigate', =>
           @text "#{frame.rawPath} @ #{frame.lineNumber}"
       @div class: 'panel-body padded', outlet: 'body', =>
-        @pre output: 'source', 'Source goes here'
+        @pre outlet: 'source', 'Source goes here'
 
   initialize: (@frame) ->
 
diff --git a/spec/fixtures/context.txt b/spec/fixtures/context.txt
new file mode 100644
index 0000000..d6a16bf
--- /dev/null
+++ b/spec/fixtures/context.txt
@@ -0,0 +1,11 @@
+zero
+one
+two
+three
+four
+five
+six
+seven
+eight
+nine
+ten
diff --git a/spec/stacktrace-spec.coffee b/spec/stacktrace-spec.coffee
index 32590af..f609873 100644
--- a/spec/stacktrace-spec.coffee
+++ b/spec/stacktrace-spec.coffee
@@ -1,5 +1,6 @@
-{Stacktrace} = require '../lib/stacktrace'
+{Stacktrace, Frame} = require '../lib/stacktrace'
 {RUBY: {FUNCTION: TRACE}} = require './trace-fixtures'
+require 'path'
 
 describe 'Stacktrace', ->
   describe 'with a Ruby trace', ->
@@ -72,3 +73,25 @@ describe 'Stacktrace', ->
         expect(Stacktrace.forUrl(trace.getUrl())).toBe(trace)
         trace.unregister()
         expect(Stacktrace.forUrl(trace.getUrl())).toBeUndefined()
+
+describe 'Frame', ->
+  [frame] = []
+
+  beforeEach ->
+    fixturePath = path.join __dirname, 'fixtures', 'context.txt'
+    frame = new Frame('five', fixturePath, 5, 'something')
+
+  it 'acquires n lines of context asynchronously', ->
+    lines = null
+
+    frame.getContext 2, (ls) -> lines = ls
+
+    waitsFor -> lines?
+
+    runs ->
+      expect(lines.length).toBe(5)
+      expect(lines[0]).toEqual('three')
+      expect(lines[1]).toEqual('four')
+      expect(lines[2]).toEqual('five')
+      expect(lines[3]).toEqual('six')
+      expect(lines[4]).toEqual('seven')

From d6d40418f40ca628ae0d95066d7790ec6db7b98e Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 08:35:05 -0400
Subject: [PATCH 09/22] Use line-chomper to read files by lines.

---
 package.json | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index ee63d0d..6db1235 100644
--- a/package.json
+++ b/package.json
@@ -12,6 +12,7 @@
     "atom": ">0.50.0"
   },
   "dependencies": {
-    "jssha": "^1.5.0"
+    "jssha": "^1.5.0",
+    "line-chomper": "^0.4.4"
   }
 }

From 701598c7617d927318389e4ec620443daff57b6d Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 08:47:06 -0400
Subject: [PATCH 10/22] Implement Frame.getContext().

---
 lib/stacktrace.coffee       | 17 ++++++++++++++++-
 spec/stacktrace-spec.coffee |  7 +++++--
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/lib/stacktrace.coffee b/lib/stacktrace.coffee
index 0895f7c..ef6e32a 100644
--- a/lib/stacktrace.coffee
+++ b/lib/stacktrace.coffee
@@ -1,4 +1,6 @@
+fs = require 'fs'
 jsSHA = require 'jssha'
+{chomp} = require 'line-chomper'
 traceParser = null
 
 PREFIX = 'stacktrace://trace'
@@ -56,13 +58,26 @@ class Stacktrace
   @clearRegistry: ->
     REGISTRY = {}
 
-# Internal: A single stack frame within a {Stacktrace}.
+# Public: A single stack frame within a {Stacktrace}.
 #
 class Frame
 
   constructor: (@rawLine, @rawPath, @lineNumber, @functionName) ->
     @realPath = @rawPath
 
+  # Public: Asynchronously collect n lines of context around the specified line number in this
+  # frame's source file.
+  #
+  # n        - The number of lines of context to collect on *each* side of the error line. The error
+  #            line will always be `lines[n]` and `lines.length` will be `n * 2 + 1`.
+  # callback - Invoked with any errors or an Array containing the relevant lines.
+  #
+  getContext: (n, callback) ->
+    range =
+      fromLine: @lineNumber - n
+      toLine: @lineNumber + n + 1
+    chomp fs.createReadStream(@realPath), range, callback
+
 module.exports =
   PREFIX: PREFIX
   Stacktrace: Stacktrace
diff --git a/spec/stacktrace-spec.coffee b/spec/stacktrace-spec.coffee
index f609873..cfc97f5 100644
--- a/spec/stacktrace-spec.coffee
+++ b/spec/stacktrace-spec.coffee
@@ -1,6 +1,7 @@
+path = require 'path'
+
 {Stacktrace, Frame} = require '../lib/stacktrace'
 {RUBY: {FUNCTION: TRACE}} = require './trace-fixtures'
-require 'path'
 
 describe 'Stacktrace', ->
   describe 'with a Ruby trace', ->
@@ -84,7 +85,9 @@ describe 'Frame', ->
   it 'acquires n lines of context asynchronously', ->
     lines = null
 
-    frame.getContext 2, (ls) -> lines = ls
+    frame.getContext 2, (err, ls) ->
+      throw err if err?
+      lines = ls
 
     waitsFor -> lines?
 

From b306d95ef68a576752c88ddc4b23eca986fd8642 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 09:30:10 -0400
Subject: [PATCH 11/22] Use my line-chomper fork.

So I can disable the automatic `.trim()`.
---
 lib/stacktrace.coffee       | 2 ++
 package.json                | 2 +-
 spec/fixtures/context.txt   | 4 ++--
 spec/stacktrace-spec.coffee | 4 ++--
 4 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/stacktrace.coffee b/lib/stacktrace.coffee
index ef6e32a..f14a9a3 100644
--- a/lib/stacktrace.coffee
+++ b/lib/stacktrace.coffee
@@ -76,6 +76,8 @@ class Frame
     range =
       fromLine: @lineNumber - n
       toLine: @lineNumber + n + 1
+      trim: false
+      keepLastEmptyLine: true
     chomp fs.createReadStream(@realPath), range, callback
 
 module.exports =
diff --git a/package.json b/package.json
index 6db1235..6f45385 100644
--- a/package.json
+++ b/package.json
@@ -13,6 +13,6 @@
   },
   "dependencies": {
     "jssha": "^1.5.0",
-    "line-chomper": "^0.4.4"
+    "line-chomper": "git+https://github.com/smashwilson/line-chomper.git#optional-trim"
   }
 }
diff --git a/spec/fixtures/context.txt b/spec/fixtures/context.txt
index d6a16bf..b02e70e 100644
--- a/spec/fixtures/context.txt
+++ b/spec/fixtures/context.txt
@@ -2,10 +2,10 @@ zero
 one
 two
 three
-four
+  four
 five
 six
-seven
+
 eight
 nine
 ten
diff --git a/spec/stacktrace-spec.coffee b/spec/stacktrace-spec.coffee
index cfc97f5..43865c2 100644
--- a/spec/stacktrace-spec.coffee
+++ b/spec/stacktrace-spec.coffee
@@ -94,7 +94,7 @@ describe 'Frame', ->
     runs ->
       expect(lines.length).toBe(5)
       expect(lines[0]).toEqual('three')
-      expect(lines[1]).toEqual('four')
+      expect(lines[1]).toEqual('  four')
       expect(lines[2]).toEqual('five')
       expect(lines[3]).toEqual('six')
-      expect(lines[4]).toEqual('seven')
+      expect(lines[4]).toEqual('')

From 840d8630dc85509915d00299be8ae77d34e258e7 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 09:32:03 -0400
Subject: [PATCH 12/22] Use a mini-EditorView to show code snippets.

---
 lib/stacktrace-view.coffee  | 9 +++++++--
 stylesheets/stacktrace.less | 2 ++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index 83da43e..5ce705a 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -1,4 +1,4 @@
-{View} = require 'atom'
+{View, EditorView} = require 'atom'
 {Stacktrace, PREFIX} = require './stacktrace'
 
 class StacktraceView extends View
@@ -55,9 +55,14 @@ class FrameView extends View
         @span class: 'source-location text-info inline-block pull-right', click: 'navigate', =>
           @text "#{frame.rawPath} @ #{frame.lineNumber}"
       @div class: 'panel-body padded', outlet: 'body', =>
-        @pre outlet: 'source', 'Source goes here'
+        @subview 'source', new EditorView(mini: true)
 
   initialize: (@frame) ->
+    @frame.getContext 3, (err, lines) =>
+      if err?
+        console.error err
+      else
+        @source.getEditor().setText lines.join("\n")
 
   navigate: ->
     console.log "Navigate"
diff --git a/stylesheets/stacktrace.less b/stylesheets/stacktrace.less
index 5fb9d0c..ea41167 100644
--- a/stylesheets/stacktrace.less
+++ b/stylesheets/stacktrace.less
@@ -19,6 +19,8 @@
   }
 
   .frame {
+    margin-bottom: 10px;
+
     .icon-fold, .icon-unfold {
       cursor: pointer;
     }

From 70d5e3bb5f08c9c2c2a09f6105c3427937471c2a Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 09:37:53 -0400
Subject: [PATCH 13/22] Hey look an off-by-one error

---
 lib/stacktrace.coffee     | 5 +++--
 spec/fixtures/context.txt | 1 -
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/stacktrace.coffee b/lib/stacktrace.coffee
index f14a9a3..861a7b4 100644
--- a/lib/stacktrace.coffee
+++ b/lib/stacktrace.coffee
@@ -73,9 +73,10 @@ class Frame
   # callback - Invoked with any errors or an Array containing the relevant lines.
   #
   getContext: (n, callback) ->
+    # Notice that @lineNumber is one-indexed, not zero-indexed.
     range =
-      fromLine: @lineNumber - n
-      toLine: @lineNumber + n + 1
+      fromLine: @lineNumber - n - 1
+      toLine: @lineNumber + n
       trim: false
       keepLastEmptyLine: true
     chomp fs.createReadStream(@realPath), range, callback
diff --git a/spec/fixtures/context.txt b/spec/fixtures/context.txt
index b02e70e..5a3ecb4 100644
--- a/spec/fixtures/context.txt
+++ b/spec/fixtures/context.txt
@@ -1,4 +1,3 @@
-zero
 one
 two
 three

From 3bf2b3cbca2e3197511887fafd74472f0ed95f47 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:01:48 -0400
Subject: [PATCH 14/22] Navigate to a specific Frame.

---
 lib/stacktrace-view.coffee |  3 +--
 lib/stacktrace.coffee      | 11 +++++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index 5ce705a..df00dbc 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -64,8 +64,7 @@ class FrameView extends View
       else
         @source.getEditor().setText lines.join("\n")
 
-  navigate: ->
-    console.log "Navigate"
+  navigate: -> @frame.navigateTo()
 
   minimize: ->
     @addClass 'minimized'
diff --git a/lib/stacktrace.coffee b/lib/stacktrace.coffee
index 861a7b4..75e9356 100644
--- a/lib/stacktrace.coffee
+++ b/lib/stacktrace.coffee
@@ -81,6 +81,17 @@ class Frame
       keepLastEmptyLine: true
     chomp fs.createReadStream(@realPath), range, callback
 
+  navigateTo: ->
+    position = [@lineNumber - 1, 0]
+    promise = atom.workspace.open @realPath, initialLine: position[0]
+    promise.then (editor) ->
+      editor.setCursorBufferPosition position
+      for ev in atom.workspaceView.getEditorViews()
+        editorView = ev if ev.getEditor() is editor
+      if editorView?
+        editorView.scrollToBufferPosition position, center: true
+
+
 module.exports =
   PREFIX: PREFIX
   Stacktrace: Stacktrace

From 267140a1befd028d2bed947cefadff3208584c9e Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:04:46 -0400
Subject: [PATCH 15/22] Navigate on a click anywhere in the frame.

I'm not so sure about this one.
---
 lib/stacktrace-view.coffee  | 2 +-
 stylesheets/stacktrace.less | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index df00dbc..ad25767 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -54,7 +54,7 @@ class FrameView extends View
         @span class: 'function-name text-highlight inline-block', frame.functionName
         @span class: 'source-location text-info inline-block pull-right', click: 'navigate', =>
           @text "#{frame.rawPath} @ #{frame.lineNumber}"
-      @div class: 'panel-body padded', outlet: 'body', =>
+      @div class: 'panel-body padded', outlet: 'body', click: 'navigate', =>
         @subview 'source', new EditorView(mini: true)
 
   initialize: (@frame) ->
diff --git a/stylesheets/stacktrace.less b/stylesheets/stacktrace.less
index ea41167..6e1f365 100644
--- a/stylesheets/stacktrace.less
+++ b/stylesheets/stacktrace.less
@@ -31,6 +31,10 @@
       .icon-unfold { display: inline-block; }
       .icon-fold { display: none; }
     }
+
+    .editor {
+      cursor: pointer;
+    }
   }
 
   &.activated {

From c7f9779d893a868bae86f5156770070d35bc3aa0 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:11:56 -0400
Subject: [PATCH 16/22] Mark the currently "active" Stacktrace.

---
 lib/stacktrace.coffee       | 14 ++++++++++++++
 spec/stacktrace-spec.coffee | 18 ++++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/lib/stacktrace.coffee b/lib/stacktrace.coffee
index 75e9356..8cfe6ad 100644
--- a/lib/stacktrace.coffee
+++ b/lib/stacktrace.coffee
@@ -6,6 +6,7 @@ traceParser = null
 PREFIX = 'stacktrace://trace'
 
 REGISTRY = {}
+ACTIVE = null
 
 # Internal: A heuristically parsed and interpreted stacktrace.
 #
@@ -41,6 +42,15 @@ class Stacktrace
   unregister: ->
     delete REGISTRY[@getUrl()]
 
+  # Public: Mark this trace as the "active" one. The active trace is shown in the navigation view
+  # and its frames are given a marker in an open {EditorView}.
+  #
+  activate: -> ACTIVE = this
+
+  # Public: Deactivate this trace if it's active.
+  #
+  deactivate: -> ACTIVE = null if ACTIVE is this
+
   # Public: Parse zero to many Stacktrace instances from a corpus of text.
   #
   # text - A raw blob of text.
@@ -58,6 +68,10 @@ class Stacktrace
   @clearRegistry: ->
     REGISTRY = {}
 
+  # Public: Retrieve the currently activated {Stacktrace}, or null if no trace is active.
+  #
+  @getActivated: -> ACTIVE
+
 # Public: A single stack frame within a {Stacktrace}.
 #
 class Frame
diff --git a/spec/stacktrace-spec.coffee b/spec/stacktrace-spec.coffee
index 43865c2..c500118 100644
--- a/spec/stacktrace-spec.coffee
+++ b/spec/stacktrace-spec.coffee
@@ -75,6 +75,24 @@ describe 'Stacktrace', ->
         trace.unregister()
         expect(Stacktrace.forUrl(trace.getUrl())).toBeUndefined()
 
+    describe 'activation', ->
+      afterEach ->
+        activated = Stacktrace.getActivated()
+        activated.deactivate() if activated?
+
+      it 'can be activated', ->
+        trace.activate()
+        expect(Stacktrace.getActivated()).toBe(trace)
+
+      it 'can be deactivated if activated', ->
+        trace.activate()
+        trace.deactivate()
+        expect(Stacktrace.getActivated()).toBeNull()
+
+      it 'can be deactivated even if not activated', ->
+        trace.deactivate()
+        expect(Stacktrace.getActivated()).toBeNull()
+
 describe 'Frame', ->
   [frame] = []
 

From 6f338d56629a2670d51e49c45780600395eb9df2 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:13:16 -0400
Subject: [PATCH 17/22] Wire up the activate and deactivate events.

---
 lib/stacktrace-view.coffee | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index ad25767..85e178d 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -27,13 +27,11 @@ class StacktraceView extends View
 
   # Public: Activate the current {Stacktrace}.
   #
-  activate: ->
-    console.log 'Activate'
+  activate: -> @trace.activate()
 
   # Public: Deactivate the current {Stacktrace}.
   #
-  deactivate: ->
-    console.log 'Deactivate'
+  deactivate: -> @trace.deactivate()
 
   # Internal: Register an opener function in the workspace to handle URLs
   # generated by a Stacktrace.

From b7de2992c8364ab568e3fcf7afb065cb0dbe4e5d Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:18:25 -0400
Subject: [PATCH 18/22] Depend on Emissary for event stuff.

---
 package.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package.json b/package.json
index 6f45385..794962d 100644
--- a/package.json
+++ b/package.json
@@ -12,6 +12,7 @@
     "atom": ">0.50.0"
   },
   "dependencies": {
+    "emissary": "^1.2.1",
     "jssha": "^1.5.0",
     "line-chomper": "git+https://github.com/smashwilson/line-chomper.git#optional-trim"
   }

From 28b8eaec96e45abf83225362d77aa46b5814bdb7 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:20:53 -0400
Subject: [PATCH 19/22] Emit events when the active Stacktrace is changed.

---
 lib/stacktrace.coffee       | 17 +++++++++++++++--
 spec/stacktrace-spec.coffee |  9 +++++++++
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/lib/stacktrace.coffee b/lib/stacktrace.coffee
index 8cfe6ad..413f38e 100644
--- a/lib/stacktrace.coffee
+++ b/lib/stacktrace.coffee
@@ -1,4 +1,7 @@
 fs = require 'fs'
+
+{Emitter} = require 'emissary'
+
 jsSHA = require 'jssha'
 {chomp} = require 'line-chomper'
 traceParser = null
@@ -12,6 +15,9 @@ ACTIVE = null
 #
 class Stacktrace
 
+  # Turn the Stacktrace class into an emitter.
+  Emitter.extend this
+
   constructor: (@frames = [], @message = '') ->
 
   # Internal: Compute the SHA256 checksum of the normalized stacktrace.
@@ -45,11 +51,18 @@ class Stacktrace
   # Public: Mark this trace as the "active" one. The active trace is shown in the navigation view
   # and its frames are given a marker in an open {EditorView}.
   #
-  activate: -> ACTIVE = this
+  activate: ->
+    former = ACTIVE
+    ACTIVE = this
+    if former isnt ACTIVE
+      Stacktrace.emit 'active-changed', oldTrace: former, newTrace: ACTIVE
 
   # Public: Deactivate this trace if it's active.
   #
-  deactivate: -> ACTIVE = null if ACTIVE is this
+  deactivate: ->
+    if ACTIVE is this
+      ACTIVE = null
+      Stacktrace.emit 'active-changed', oldTrace: this, newTrace: null
 
   # Public: Parse zero to many Stacktrace instances from a corpus of text.
   #
diff --git a/spec/stacktrace-spec.coffee b/spec/stacktrace-spec.coffee
index c500118..f6cd82e 100644
--- a/spec/stacktrace-spec.coffee
+++ b/spec/stacktrace-spec.coffee
@@ -79,6 +79,7 @@ describe 'Stacktrace', ->
       afterEach ->
         activated = Stacktrace.getActivated()
         activated.deactivate() if activated?
+        Stacktrace.off 'active-changed'
 
       it 'can be activated', ->
         trace.activate()
@@ -93,6 +94,14 @@ describe 'Stacktrace', ->
         trace.deactivate()
         expect(Stacktrace.getActivated()).toBeNull()
 
+      it 'broadcasts a "active-changed" event', ->
+        event = null
+        Stacktrace.on 'active-changed', (e) -> event = e
+
+        trace.activate()
+        expect(event.oldTrace).toBeNull()
+        expect(event.newTrace).toBe(trace)
+
 describe 'Frame', ->
   [frame] = []
 

From 1850e30a6712ce10db6ace8e9b00602a1dd2ca6a Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:32:18 -0400
Subject: [PATCH 20/22] Toggle the StacktraceView class on activation.

---
 lib/stacktrace-view.coffee       | 11 ++++++++++-
 spec/stacktrace-view-spec.coffee |  6 ++++++
 stylesheets/stacktrace.less      |  6 +++---
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index 85e178d..92d5d97 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -1,10 +1,14 @@
 {View, EditorView} = require 'atom'
+{Subscriber} = require 'emissary'
+
 {Stacktrace, PREFIX} = require './stacktrace'
 
 class StacktraceView extends View
 
+  Subscriber.includeInto this
+
   @content: (trace) ->
-    tclass = if trace.isActive() then 'activated' else 'deactivated'
+    tclass = if trace.isActive() then 'activated' else ''
     @div class: "stacktrace tool-panel padded #{tclass}", =>
       @div class: 'panel padded', =>
         @h2 class: 'error-message', trace.message
@@ -19,6 +23,11 @@ class StacktraceView extends View
           @subview 'frame', new FrameView(frame)
 
   initialize: (@trace) ->
+    @subscribe Stacktrace, 'active-changed', (e) =>
+      if e.newTrace is @trace
+        @addClass 'activated'
+      else
+        @removeClass 'activated'
 
   # Internal: Return the window title.
   #
diff --git a/spec/stacktrace-view-spec.coffee b/spec/stacktrace-view-spec.coffee
index e726f4f..83b7fa3 100644
--- a/spec/stacktrace-view-spec.coffee
+++ b/spec/stacktrace-view-spec.coffee
@@ -37,6 +37,12 @@ describe 'StacktraceView', ->
     vs = view.find('.frame')
     expect(vs.length).toBe(3)
 
+  it 'changes its class when its trace is activated or deactivated', ->
+    Stacktrace.getActivated()?.deactivate()
+    expect(view.hasClass 'activated').toBe(false)
+    trace.activate()
+    expect(view.hasClass 'activated').toBe(true)
+
 describe 'FrameView', ->
   [view] = []
 
diff --git a/stylesheets/stacktrace.less b/stylesheets/stacktrace.less
index 6e1f365..282fe3c 100644
--- a/stylesheets/stacktrace.less
+++ b/stylesheets/stacktrace.less
@@ -37,11 +37,11 @@
     }
   }
 
+  .deactivate-control { display: none; }
+
   &.activated {
+    .deactivate-control { display: block; }
     .activate-control { display: none; }
   }
 
-  &.deactivated {
-    .deactivate-control { display: none; }
-  }
 }

From 1190bcec5429516d13299d62dff01d4f65249c7c Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:39:53 -0400
Subject: [PATCH 21/22] Activate the Stacktrace on navigation.

---
 lib/stacktrace-view.coffee       | 10 ++++++----
 spec/stacktrace-view-spec.coffee |  2 +-
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index 92d5d97..db0dc7c 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -20,7 +20,7 @@ class StacktraceView extends View
           @span class: 'inline-block', 'to close the stacktrace navigation panel.'
       @div class: 'frames', =>
         for frame in trace.frames
-          @subview 'frame', new FrameView(frame)
+          @subview 'frame', new FrameView frame, => trace.activate()
 
   initialize: (@trace) ->
     @subscribe Stacktrace, 'active-changed', (e) =>
@@ -53,7 +53,7 @@ class StacktraceView extends View
 
 class FrameView extends View
 
-  @content: (frame) ->
+  @content: (frame, navCallback) ->
     @div class: 'frame inset-panel', =>
       @div class: 'panel-heading', =>
         @span class: 'icon icon-fold inline-block', click: 'minimize'
@@ -64,14 +64,16 @@ class FrameView extends View
       @div class: 'panel-body padded', outlet: 'body', click: 'navigate', =>
         @subview 'source', new EditorView(mini: true)
 
-  initialize: (@frame) ->
+  initialize: (@frame, @navCallback) ->
     @frame.getContext 3, (err, lines) =>
       if err?
         console.error err
       else
         @source.getEditor().setText lines.join("\n")
 
-  navigate: -> @frame.navigateTo()
+  navigate: ->
+    @navCallback()
+    @frame.navigateTo()
 
   minimize: ->
     @addClass 'minimized'
diff --git a/spec/stacktrace-view-spec.coffee b/spec/stacktrace-view-spec.coffee
index 83b7fa3..c6895fd 100644
--- a/spec/stacktrace-view-spec.coffee
+++ b/spec/stacktrace-view-spec.coffee
@@ -47,7 +47,7 @@ describe 'FrameView', ->
   [view] = []
 
   beforeEach ->
-    view = new FrameView(frames[1])
+    view = new FrameView frames[1], ->
 
   it 'shows the filename and line number', ->
     text = view.find('.source-location').text()

From 12db0695f797895f3b0aba6b27f86ed75a3df2e3 Mon Sep 17 00:00:00 2001
From: Ash Wilson <smashwilson@gmail.com>
Date: Sun, 27 Jul 2014 11:41:47 -0400
Subject: [PATCH 22/22] Unsubscribe on view close.

---
 lib/stacktrace-view.coffee | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/stacktrace-view.coffee b/lib/stacktrace-view.coffee
index db0dc7c..bda2d1f 100644
--- a/lib/stacktrace-view.coffee
+++ b/lib/stacktrace-view.coffee
@@ -29,6 +29,9 @@ class StacktraceView extends View
       else
         @removeClass 'activated'
 
+  beforeRemove: ->
+    @unsubscribe Stacktrace
+
   # Internal: Return the window title.
   #
   getTitle: ->