Add edge case tests of barplot

Author: mrkn

lib/unicode_plot/barplot.rb

@@ -97,6 +97,13 @@ def print_row(out, row_index)
       raise ArgumentError, "invalid arguments"
     end
 
+    unless keys.length == heights.length
+      raise ArgumentError, "The given vectors must be of the same length"
+    end
+    unless heights.min >= 0
+      raise ArgumentError, "All values have to be positive. Negative bars are not supported."
+    end
+
     xlabel ||= ValueTransformer.transform_name(xscale)
     plot = Barplot.new(heights, width, color, symbol, xscale,
                        border: border, xlabel: xlabel,
@@ -130,6 +137,7 @@ def print_row(out, row_index)
     if keys.empty?
       raise ArgumentError, "Can't append empty array to barplot"
     end
+
     cur_idx = plot.n_rows
     plot.add_row!(heights)
     keys.each_with_index do |key, i|

test/fixtures/barplot/edgecase_onelarge.txt

@@ -0,0 +1,6 @@
+     ┌                                        ┐ 
+   a ┤ 1                                        
+   b ┤ 1                                        
+   c ┤ 1                                        
+   d ┤■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■ 1000000   
+     └                                        ┘ 

test/fixtures/barplot/edgecase_zeros.txt

@@ -0,0 +1,7 @@
+     ┌                                        ┐ 
+   5 ┤ 0                                        
+   4 ┤ 0                                        
+   3 ┤ 0                                        
+   2 ┤ 0                                        
+   1 ┤ 0                                        
+     └                                        ┘ 

test/test-barplot.rb

@@ -3,6 +3,15 @@ class BarplotTest < Test::Unit::TestCase
   include Helper::WithTerm
 
   sub_test_case("UnicodePlot.barplot") do
+    test("errors") do
+      assert_raise(ArgumentError) do
+        UnicodePlot.barplot([:a], [-1, 2])
+      end
+      assert_raise(ArgumentError) do
+        UnicodePlot.barplot([:a, :b], [-1, 2])
+      end
+    end
+
     test("colored") do
       data = { bar: 23, foo: 37 }
       plot = UnicodePlot.barplot(data: data)
@@ -69,6 +78,20 @@ class BarplotTest < Test::Unit::TestCase
       assert_equal(fixture_path("barplot/ranges.txt").read,
                    output)
     end
+
+    test("all zeros") do
+      plot = UnicodePlot.barplot([5, 4, 3, 2, 1], [0, 0, 0, 0, 0])
+      _, output = with_term { plot.render($stdout) }
+      assert_equal(fixture_path("barplot/edgecase_zeros.txt").read,
+                   output)
+    end
+
+    test("one large") do
+      plot = UnicodePlot.barplot([:a, :b, :c, :d], [1, 1, 1, 1000000])
+      _, output = with_term { plot.render($stdout) }
+      assert_equal(fixture_path("barplot/edgecase_onelarge.txt").read,
+                   output)
+    end
   end
 
   sub_test_case("UnicodePlot.barplot!") do