diff options
Diffstat (limited to 'lib/experimental/diff.nim')
| -rw-r--r-- | lib/experimental/diff.nim | 58 |
1 files changed, 32 insertions, 26 deletions
diff --git a/lib/experimental/diff.nim b/lib/experimental/diff.nim index 1db891440..669e9f613 100644 --- a/lib/experimental/diff.nim +++ b/lib/experimental/diff.nim @@ -10,28 +10,31 @@ ## This module implements an algorithm to compute the ## `diff`:idx: between two sequences of lines. ## -## A basic example of `diffInt` on 2 arrays of integers: -## -## .. code::nim -## -## import experimental/diff -## echo diffInt([0, 1, 2, 3, 4, 5, 6, 7, 8], [-1, 1, 2, 3, 4, 5, 666, 7, 42]) -## -## Another short example of `diffText` to diff strings: -## -## .. code::nim -## -## import experimental/diff -## # 2 samples of text for testing (from "The Call of Cthulhu" by Lovecraft) -## let txt0 = """I have looked upon all the universe has to hold of horror, -## even skies of spring and flowers of summer must ever be poison to me.""" -## let txt1 = """I have looked upon all your code has to hold of bugs, -## even skies of spring and flowers of summer must ever be poison to me.""" -## -## echo diffText(txt0, txt1) -## ## - To learn more see `Diff on Wikipedia. <http://wikipedia.org/wiki/Diff>`_ +runnableExamples: + assert diffInt( + [0, 1, 2, 3, 4, 5, 6, 7, 8], + [-1, 1, 2, 3, 4, 5, 666, 7, 42]) == + @[Item(startA: 0, startB: 0, deletedA: 1, insertedB: 1), + Item(startA: 6, startB: 6, deletedA: 1, insertedB: 1), + Item(startA: 8, startB: 8, deletedA: 1, insertedB: 1)] + +runnableExamples: + # 2 samples of text (from "The Call of Cthulhu" by Lovecraft) + let txt0 = """ +abc +def ghi +jkl2""" + let txt1 = """ +bacx +abc +def ghi +jkl""" + assert diffText(txt0, txt1) == + @[Item(startA: 0, startB: 0, deletedA: 0, insertedB: 1), + Item(startA: 2, startB: 3, deletedA: 1, insertedB: 1)] + # code owner: Arne Döring # # This is based on C# code written by Matthias Hertel, http://www.mathertel.de @@ -40,7 +43,10 @@ # "An O(ND) Difference Algorithm and its Variations" by Eugene Myers # Algorithmica Vol. 1 No. 2, 1986, p 251. -import tables, strutils +import std/[tables, strutils] + +when defined(nimPreviewSlimSystem): + import std/assertions type Item* = object ## An Item in the list of differences. @@ -288,9 +294,9 @@ proc diffInt*(arrayA, arrayB: openArray[int]): seq[Item] = var dataB = newDiffData(@arrayB, arrayB.len) let max = dataA.len + dataB.len + 1 - ## vector for the (0,0) to (x,y) search + # vector for the (0,0) to (x,y) search var downVector = newSeq[int](2 * max + 2) - ## vector for the (u,v) to (N,M) search + # vector for the (u,v) to (N,M) search var upVector = newSeq[int](2 * max + 2) lcs(dataA, 0, dataA.len, dataB, 0, dataB.len, downVector, upVector) @@ -309,7 +315,7 @@ proc diffText*(textA, textB: string): seq[Item] = ## `textB` B-version of the text (usually the new one) ## ## Returns a seq of Items that describe the differences. - + # See also `gitutils.diffStrings`. # prepare the input-text and convert to comparable numbers. var h = initTable[string, int]() # TextA.len + TextB.len <- probably wrong initial size # The A-Version of the data (original data) to be compared. @@ -321,9 +327,9 @@ proc diffText*(textA, textB: string): seq[Item] = h.clear # free up hashtable memory (maybe) let max = dataA.len + dataB.len + 1 - ## vector for the (0,0) to (x,y) search + # vector for the (0,0) to (x,y) search var downVector = newSeq[int](2 * max + 2) - ## vector for the (u,v) to (N,M) search + # vector for the (u,v) to (N,M) search var upVector = newSeq[int](2 * max + 2) lcs(dataA, 0, dataA.len, dataB, 0, dataB.len, downVector, upVector) |