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<pre><a name="line-1"></a><span class='hs-comment'>-- Copyright (C) 2005 David Roundy</span>
<a name="line-2"></a><span class='hs-comment'>--</span>
<a name="line-3"></a><span class='hs-comment'>-- This file is licensed under the GPL, version two or later.</span>
<a name="line-4"></a>
<a name="line-5"></a><span class='hs-comment'>{-# LANGUAGE CPP #-}</span>
<a name="line-6"></a>
<a name="line-7"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Repository</span><span class='hs-varop'>.</span><span class='hs-conid'>Format</span> <span class='hs-layout'>(</span> <span class='hs-conid'>RepoFormat</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-conid'>RepoProperty</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span>
<a name="line-8"></a> <span class='hs-varid'>identifyRepoFormat</span><span class='hs-layout'>,</span> <span class='hs-varid'>tryIdentifyRepoFormat</span><span class='hs-layout'>,</span>
<a name="line-9"></a> <span class='hs-varid'>createRepoFormat</span><span class='hs-layout'>,</span> <span class='hs-varid'>writeRepoFormat</span><span class='hs-layout'>,</span>
<a name="line-10"></a> <span class='hs-varid'>writeProblem</span><span class='hs-layout'>,</span> <span class='hs-varid'>readProblem</span><span class='hs-layout'>,</span> <span class='hs-varid'>readfromAndWritetoProblem</span><span class='hs-layout'>,</span>
<a name="line-11"></a> <span class='hs-varid'>formatHas</span><span class='hs-layout'>,</span>
<a name="line-12"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-13"></a>
<a name="line-14"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span> <span class='hs-varid'>isJust</span><span class='hs-layout'>,</span> <span class='hs-varid'>mapMaybe</span> <span class='hs-layout'>)</span>
<a name="line-15"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span> <span class='hs-varid'>mplus</span><span class='hs-layout'>,</span> <span class='hs-layout'>(</span><span class='hs-varop'><=<</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-16"></a>
<a name="line-17"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>SignalHandler</span> <span class='hs-layout'>(</span> <span class='hs-varid'>catchNonSignal</span> <span class='hs-layout'>)</span>
<a name="line-18"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>External</span> <span class='hs-layout'>(</span> <span class='hs-varid'>fetchFilePS</span><span class='hs-layout'>,</span> <span class='hs-conid'>Cachable</span><span class='hs-layout'>(</span> <span class='hs-conid'>Cachable</span> <span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-19"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Flags</span> <span class='hs-layout'>(</span> <span class='hs-conid'>DarcsFlag</span> <span class='hs-layout'>(</span> <span class='hs-conid'>UseFormat2</span><span class='hs-layout'>,</span> <span class='hs-conid'>UseHashedInventory</span><span class='hs-layout'>,</span> <span class='hs-conid'>UseNoWorkingDir</span> <span class='hs-layout'>)</span> <span class='hs-layout'>)</span>
<a name="line-20"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Lock</span> <span class='hs-layout'>(</span> <span class='hs-varid'>writeBinFile</span> <span class='hs-layout'>)</span>
<a name="line-21"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Utils</span> <span class='hs-layout'>(</span> <span class='hs-varid'>catchall</span><span class='hs-layout'>,</span> <span class='hs-varid'>prettyException</span> <span class='hs-layout'>)</span>
<a name="line-22"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Progress</span> <span class='hs-layout'>(</span> <span class='hs-varid'>beginTedious</span><span class='hs-layout'>,</span> <span class='hs-varid'>endTedious</span><span class='hs-layout'>,</span> <span class='hs-varid'>finishedOneIO</span> <span class='hs-layout'>)</span>
<a name="line-23"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Darcs</span><span class='hs-varop'>.</span><span class='hs-conid'>Global</span> <span class='hs-layout'>(</span> <span class='hs-varid'>darcsdir</span> <span class='hs-layout'>)</span>
<a name="line-24"></a>
<a name="line-25"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>ByteStringUtils</span> <span class='hs-layout'>(</span> <span class='hs-varid'>linesPS</span> <span class='hs-layout'>)</span>
<a name="line-26"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-varop'>.</span><span class='hs-conid'>Char8</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>BC</span> <span class='hs-layout'>(</span><span class='hs-varid'>split</span><span class='hs-layout'>,</span> <span class='hs-varid'>unpack</span><span class='hs-layout'>,</span> <span class='hs-varid'>singleton</span><span class='hs-layout'>,</span> <span class='hs-varid'>elemIndex</span><span class='hs-layout'>,</span> <span class='hs-varid'>pack</span><span class='hs-layout'>)</span>
<a name="line-27"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>B</span> <span class='hs-layout'>(</span><span class='hs-conid'>ByteString</span><span class='hs-layout'>,</span> <span class='hs-varid'>null</span><span class='hs-layout'>,</span> <span class='hs-varid'>empty</span><span class='hs-layout'>)</span>
<a name="line-28"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>ByteStringUtils</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>BU</span> <span class='hs-layout'>(</span> <span class='hs-varid'>intercalate</span> <span class='hs-layout'>)</span>
<a name="line-29"></a>
<a name="line-30"></a><span class='hs-cpp'>#include "impossible.h"</span>
<a name="line-31"></a>
<a name="line-32"></a><a name="RepoProperty"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>RepoProperty</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Darcs1_0</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Darcs2</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>HashedInventory</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>NoWorkingDir</span>
<a name="line-33"></a>
<a name="line-34"></a><a name="RepoFormat"></a><span class='hs-comment'>-- | @RepoFormat@ is the representation of the format of a</span>
<a name="line-35"></a><a name="RepoFormat"></a><span class='hs-comment'>-- repository. Each sublist corresponds to a line in the format</span>
<a name="line-36"></a><a name="RepoFormat"></a><span class='hs-comment'>-- file. Each line is decomposed into words.</span>
<a name="line-37"></a><a name="RepoFormat"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>RF</span> <span class='hs-keyglyph'>[</span><span class='hs-keyglyph'>[</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-keyglyph'>]</span><span class='hs-keyglyph'>]</span> <span class='hs-keyword'>deriving</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Show</span> <span class='hs-layout'>)</span>
<a name="line-38"></a>
<a name="line-39"></a><a name="df"></a><span class='hs-comment'>-- | The file where the format information should be.</span>
<a name="line-40"></a><span class='hs-definition'>df</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FilePath</span>
<a name="line-41"></a><span class='hs-definition'>df</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>darcsdir</span><span class='hs-varop'>++</span><span class='hs-str'>"/format"</span>
<a name="line-42"></a>
<a name="line-43"></a><a name="identifyRepoFormat"></a><span class='hs-comment'>-- | @identifyRepoFormat URL@ identifies the format of the repository</span>
<a name="line-44"></a><span class='hs-comment'>-- at the given address. Fails if we weren't able to identify the format.</span>
<a name="line-45"></a><span class='hs-definition'>identifyRepoFormat</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>RepoFormat</span>
<a name="line-46"></a><span class='hs-definition'>identifyRepoFormat</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>either</span> <span class='hs-varid'>fail</span> <span class='hs-varid'>return</span> <span class='hs-varop'><=<</span> <span class='hs-varid'>tryIdentifyRepoFormat</span>
<a name="line-47"></a>
<a name="line-48"></a><a name="tryIdentifyRepoFormat"></a><span class='hs-comment'>-- | @tryIdentifyRepoFormat URL@ identifies the format of the repository</span>
<a name="line-49"></a><span class='hs-comment'>-- at the given address. Return @Left reason@ if it fails, where</span>
<a name="line-50"></a><span class='hs-comment'>-- @reason@ explains why we weren't able to identify the format.</span>
<a name="line-51"></a><span class='hs-definition'>tryIdentifyRepoFormat</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>Either</span> <span class='hs-conid'>String</span> <span class='hs-conid'>RepoFormat</span><span class='hs-layout'>)</span>
<a name="line-52"></a><span class='hs-definition'>tryIdentifyRepoFormat</span> <span class='hs-varid'>repo</span> <span class='hs-keyglyph'>=</span>
<a name="line-53"></a> <span class='hs-keyword'>do</span> <span class='hs-keyword'>let</span> <span class='hs-varid'>k</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"Identifying repository "</span><span class='hs-varop'>++</span><span class='hs-varid'>repo</span>
<a name="line-54"></a> <span class='hs-varid'>beginTedious</span> <span class='hs-varid'>k</span>
<a name="line-55"></a> <span class='hs-varid'>finishedOneIO</span> <span class='hs-varid'>k</span> <span class='hs-str'>"format"</span>
<a name="line-56"></a> <span class='hs-varid'>dff</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>fetchFilePS</span> <span class='hs-layout'>(</span><span class='hs-varid'>repo</span> <span class='hs-varop'>++</span> <span class='hs-str'>"/"</span> <span class='hs-varop'>++</span> <span class='hs-varid'>df</span><span class='hs-layout'>)</span> <span class='hs-conid'>Cachable</span> <span class='hs-varop'>`catchall`</span> <span class='hs-varid'>return</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>empty</span>
<a name="line-57"></a> <span class='hs-comment'>-- below is a workaround for servers that don't return a 404 on nonexistent files</span>
<a name="line-58"></a> <span class='hs-varid'>rf</span> <span class='hs-keyglyph'><-</span> <span class='hs-keyword'>if</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>null</span> <span class='hs-varid'>dff</span> <span class='hs-varop'>||</span> <span class='hs-varid'>isJust</span> <span class='hs-layout'>(</span><span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>elemIndex</span> <span class='hs-chr'>'<'</span> <span class='hs-varid'>dff</span><span class='hs-layout'>)</span>
<a name="line-59"></a> <span class='hs-keyword'>then</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>finishedOneIO</span> <span class='hs-varid'>k</span> <span class='hs-str'>"inventory"</span>
<a name="line-60"></a> <span class='hs-varid'>have_inventory</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>doesRemoteFileExist</span> <span class='hs-layout'>(</span><span class='hs-varid'>repo</span><span class='hs-varop'>++</span><span class='hs-str'>"/"</span><span class='hs-varop'>++</span><span class='hs-varid'>darcsdir</span><span class='hs-varop'>++</span><span class='hs-str'>"/inventory"</span><span class='hs-layout'>)</span>
<a name="line-61"></a> <span class='hs-varid'>return</span> <span class='hs-varop'>$</span>
<a name="line-62"></a> <span class='hs-keyword'>case</span> <span class='hs-varid'>have_inventory</span> <span class='hs-keyword'>of</span>
<a name="line-63"></a> <span class='hs-conid'>Right</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Right</span> <span class='hs-varid'>defaultRepoFormat</span>
<a name="line-64"></a> <span class='hs-conid'>Left</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Left</span> <span class='hs-varop'>.</span> <span class='hs-varid'>unlines</span> <span class='hs-varop'>$</span>
<a name="line-65"></a> <span class='hs-keyglyph'>[</span> <span class='hs-str'>"Not a repository: "</span><span class='hs-varop'>++</span><span class='hs-varid'>repo</span><span class='hs-varop'>++</span><span class='hs-str'>" ("</span><span class='hs-varop'>++</span><span class='hs-varid'>e</span><span class='hs-varop'>++</span><span class='hs-str'>")"</span>
<a name="line-66"></a> <span class='hs-layout'>,</span> <span class='hs-str'>""</span>
<a name="line-67"></a> <span class='hs-layout'>,</span> <span class='hs-str'>"HINT: Do you have the right URI for the repository?"</span>
<a name="line-68"></a> <span class='hs-layout'>,</span> <span class='hs-str'>""</span>
<a name="line-69"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" If so, check with the repository owner to see if the following files"</span>
<a name="line-70"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" are readable:"</span>
<a name="line-71"></a> <span class='hs-layout'>,</span> <span class='hs-str'>""</span>
<a name="line-72"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" 1. _darcs/format - might not exist; that's OK"</span>
<a name="line-73"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" 2. _darcs/inventory - should exist if #1 is missing"</span>
<a name="line-74"></a> <span class='hs-layout'>,</span> <span class='hs-str'>" 3. _darcs/hashed_inventory - should exist if #2 is missing"</span>
<a name="line-75"></a> <span class='hs-keyglyph'>]</span>
<a name="line-76"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>return</span> <span class='hs-varop'>$</span> <span class='hs-conid'>Right</span> <span class='hs-varop'>$</span> <span class='hs-varid'>parseRepoFormat</span> <span class='hs-varid'>dff</span>
<a name="line-77"></a> <span class='hs-varid'>endTedious</span> <span class='hs-varid'>k</span>
<a name="line-78"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>rf</span>
<a name="line-79"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>drfe</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fetchFilePS</span> <span class='hs-varid'>x</span> <span class='hs-conid'>Cachable</span> <span class='hs-varop'>>></span> <span class='hs-varid'>return</span> <span class='hs-conid'>True</span>
<a name="line-80"></a> <span class='hs-varid'>doesRemoteFileExist</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fmap</span> <span class='hs-conid'>Right</span> <span class='hs-layout'>(</span><span class='hs-varid'>drfe</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-varop'>`catchNonSignal`</span>
<a name="line-81"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>e</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-conid'>Left</span> <span class='hs-layout'>(</span><span class='hs-varid'>prettyException</span> <span class='hs-varid'>e</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-82"></a>
<a name="line-83"></a><a name="writeRepoFormat"></a><span class='hs-comment'>-- | @writeRepoFormat@ writes the repo format to the given file.</span>
<a name="line-84"></a><span class='hs-definition'>writeRepoFormat</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-85"></a><span class='hs-definition'>writeRepoFormat</span> <span class='hs-layout'>(</span><span class='hs-conid'>RF</span> <span class='hs-varid'>rf</span><span class='hs-layout'>)</span> <span class='hs-varid'>loc</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>writeBinFile</span> <span class='hs-varid'>loc</span> <span class='hs-varop'>$</span> <span class='hs-varid'>unlines</span> <span class='hs-varop'>$</span>
<a name="line-86"></a> <span class='hs-varid'>map</span> <span class='hs-layout'>(</span><span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>unpack</span> <span class='hs-varop'>.</span> <span class='hs-conid'>BU</span><span class='hs-varop'>.</span><span class='hs-varid'>intercalate</span> <span class='hs-layout'>(</span><span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>singleton</span> <span class='hs-chr'>'|'</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-varid'>rf</span>
<a name="line-87"></a>
<a name="line-88"></a><a name="parseRepoFormat"></a><span class='hs-definition'>parseRepoFormat</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>RepoFormat</span>
<a name="line-89"></a><span class='hs-definition'>parseRepoFormat</span> <span class='hs-varid'>ps</span> <span class='hs-keyglyph'>=</span>
<a name="line-90"></a> <span class='hs-conid'>RF</span> <span class='hs-varop'>$</span> <span class='hs-varid'>map</span> <span class='hs-layout'>(</span><span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>split</span> <span class='hs-chr'>'|'</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span> <span class='hs-varid'>filter</span> <span class='hs-layout'>(</span><span class='hs-varid'>not</span> <span class='hs-varop'>.</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>null</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span> <span class='hs-varid'>linesPS</span> <span class='hs-varid'>ps</span>
<a name="line-91"></a>
<a name="line-92"></a><a name="defaultRepoFormat"></a><span class='hs-comment'>-- | The repo format we assume if we do not find a format file.</span>
<a name="line-93"></a><span class='hs-definition'>defaultRepoFormat</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoFormat</span>
<a name="line-94"></a><span class='hs-definition'>defaultRepoFormat</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>RF</span> <span class='hs-keyglyph'>[</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>rp2ps</span> <span class='hs-conid'>Darcs1_0</span><span class='hs-keyglyph'>]</span><span class='hs-keyglyph'>]</span>
<a name="line-95"></a>
<a name="line-96"></a><a name="createRepoFormat"></a><span class='hs-definition'>createRepoFormat</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>DarcsFlag</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>RepoFormat</span>
<a name="line-97"></a><span class='hs-definition'>createRepoFormat</span> <span class='hs-varid'>fs</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>RF</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>rp2ps</span> <span class='hs-layout'>(</span><span class='hs-conid'>HashedInventory</span><span class='hs-conop'>:</span><span class='hs-varid'>flags2wd</span><span class='hs-layout'>)</span><span class='hs-conop'>:</span> <span class='hs-varid'>maybe2</span><span class='hs-layout'>)</span>
<a name="line-98"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>maybe2</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>if</span> <span class='hs-conid'>UseFormat2</span> <span class='hs-varop'>`notElem`</span> <span class='hs-varid'>fs</span> <span class='hs-varop'>&&</span> <span class='hs-layout'>(</span><span class='hs-conid'>UseHashedInventory</span> <span class='hs-varop'>`elem`</span> <span class='hs-varid'>fs</span><span class='hs-layout'>)</span>
<a name="line-99"></a> <span class='hs-keyword'>then</span> <span class='hs-conid'>[]</span>
<a name="line-100"></a> <span class='hs-keyword'>else</span> <span class='hs-keyglyph'>[</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>rp2ps</span> <span class='hs-conid'>Darcs2</span><span class='hs-keyglyph'>]</span><span class='hs-keyglyph'>]</span>
<a name="line-101"></a> <span class='hs-varid'>flags2wd</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>if</span> <span class='hs-conid'>UseNoWorkingDir</span> <span class='hs-varop'>`elem`</span> <span class='hs-varid'>fs</span>
<a name="line-102"></a> <span class='hs-keyword'>then</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>NoWorkingDir</span><span class='hs-keyglyph'>]</span>
<a name="line-103"></a> <span class='hs-keyword'>else</span> <span class='hs-conid'>[]</span>
<a name="line-104"></a>
<a name="line-105"></a><a name="writeProblem"></a><span class='hs-comment'>-- | @writeProblem form@ tells if we can write to a repo in format @form@.</span>
<a name="line-106"></a><span class='hs-comment'>-- It returns @Nothing@ if there's no problem writing to such a repository.</span>
<a name="line-107"></a><span class='hs-definition'>writeProblem</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-conid'>String</span>
<a name="line-108"></a><span class='hs-definition'>writeProblem</span> <span class='hs-varid'>rf</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>readProblem</span> <span class='hs-varid'>rf</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>allProblems</span> <span class='hs-varid'>rf</span> <span class='hs-varid'>wp</span>
<a name="line-109"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>wp</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>all</span> <span class='hs-varid'>isKnown</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-110"></a> <span class='hs-varid'>wp</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>impossible</span>
<a name="line-111"></a> <span class='hs-varid'>wp</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varop'>$</span> <span class='hs-varid'>unwords</span> <span class='hs-varop'>$</span> <span class='hs-str'>"Can't write repository format: "</span> <span class='hs-conop'>:</span>
<a name="line-112"></a> <span class='hs-varid'>map</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>unpack</span> <span class='hs-layout'>(</span><span class='hs-varid'>filter</span> <span class='hs-layout'>(</span><span class='hs-varid'>not</span> <span class='hs-varop'>.</span> <span class='hs-varid'>isKnown</span><span class='hs-layout'>)</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-113"></a>
<a name="line-114"></a>
<a name="line-115"></a><a name="readfromAndWritetoProblem"></a><span class='hs-comment'>-- | @readfromAndWritetoProblem form@ tells if we can read from and write to a repo in</span>
<a name="line-116"></a><span class='hs-comment'>-- format @form@. It returns @Nothing@ if there's no problem reading</span>
<a name="line-117"></a><span class='hs-comment'>-- and writing to such a repository.</span>
<a name="line-118"></a><span class='hs-definition'>readfromAndWritetoProblem</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-conid'>String</span>
<a name="line-119"></a><span class='hs-definition'>readfromAndWritetoProblem</span> <span class='hs-varid'>inrf</span> <span class='hs-varid'>outrf</span>
<a name="line-120"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>formatHas</span> <span class='hs-conid'>Darcs2</span> <span class='hs-varid'>inrf</span> <span class='hs-varop'>/=</span> <span class='hs-varid'>formatHas</span> <span class='hs-conid'>Darcs2</span> <span class='hs-varid'>outrf</span>
<a name="line-121"></a> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-str'>"Cannot mix darcs-2 repositories with older formats"</span>
<a name="line-122"></a> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>otherwise</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>readProblem</span> <span class='hs-varid'>inrf</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>writeProblem</span> <span class='hs-varid'>outrf</span>
<a name="line-123"></a>
<a name="line-124"></a>
<a name="line-125"></a><a name="readProblem"></a><span class='hs-comment'>-- | @readProblem form@ tells if we can read from a repo in format @form@.</span>
<a name="line-126"></a><span class='hs-comment'>-- It returns @Nothing@ if there's no problem reading from such a repository.</span>
<a name="line-127"></a><span class='hs-definition'>readProblem</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-conid'>String</span>
<a name="line-128"></a><span class='hs-definition'>readProblem</span> <span class='hs-varid'>rf</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>formatHas</span> <span class='hs-conid'>Darcs1_0</span> <span class='hs-varid'>rf</span> <span class='hs-varop'>&&</span> <span class='hs-varid'>formatHas</span> <span class='hs-conid'>Darcs2</span> <span class='hs-varid'>rf</span>
<a name="line-129"></a> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-str'>"Invalid repositoryformat: format 2 is incompatible with format 1"</span>
<a name="line-130"></a><span class='hs-definition'>readProblem</span> <span class='hs-varid'>rf</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>allProblems</span> <span class='hs-varid'>rf</span> <span class='hs-varid'>rp</span>
<a name="line-131"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>rp</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>any</span> <span class='hs-varid'>isKnown</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-132"></a> <span class='hs-varid'>rp</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>impossible</span>
<a name="line-133"></a> <span class='hs-varid'>rp</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varop'>$</span> <span class='hs-varid'>unwords</span> <span class='hs-varop'>$</span>
<a name="line-134"></a> <span class='hs-str'>"Can't understand repository format:"</span> <span class='hs-conop'>:</span> <span class='hs-varid'>map</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>unpack</span> <span class='hs-varid'>x</span>
<a name="line-135"></a>
<a name="line-136"></a>
<a name="line-137"></a><a name="allProblems"></a><span class='hs-definition'>allProblems</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-conid'>String</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-conid'>String</span>
<a name="line-138"></a><span class='hs-definition'>allProblems</span> <span class='hs-layout'>(</span><span class='hs-conid'>RF</span> <span class='hs-varid'>ks</span><span class='hs-layout'>)</span> <span class='hs-varid'>repoFormatLineProblem</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>maybeSingleError</span> <span class='hs-varop'>$</span> <span class='hs-varid'>mapMaybe</span> <span class='hs-varid'>repoFormatLineProblem</span> <span class='hs-varid'>ks</span>
<a name="line-139"></a> <span class='hs-keyword'>where</span>
<a name="line-140"></a> <span class='hs-varid'>maybeSingleError</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span>
<a name="line-141"></a> <span class='hs-varid'>maybeSingleError</span> <span class='hs-varid'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varop'>$</span> <span class='hs-varid'>unlines</span> <span class='hs-varid'>xs</span>
<a name="line-142"></a>
<a name="line-143"></a>
<a name="line-144"></a><a name="isKnown"></a><span class='hs-comment'>-- | Does this version of darcs know how to handle this property?</span>
<a name="line-145"></a><span class='hs-definition'>isKnown</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span>
<a name="line-146"></a><span class='hs-definition'>isKnown</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span> <span class='hs-varop'>`elem`</span> <span class='hs-varid'>map</span> <span class='hs-varid'>rp2ps</span> <span class='hs-varid'>knownProperties</span>
<a name="line-147"></a>
<a name="line-148"></a><a name="knownProperties"></a><span class='hs-comment'>-- | This is the list of properties which this version of darcs knows</span>
<a name="line-149"></a><span class='hs-comment'>-- how to handle.</span>
<a name="line-150"></a><span class='hs-definition'>knownProperties</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>RepoProperty</span><span class='hs-keyglyph'>]</span>
<a name="line-151"></a><span class='hs-definition'>knownProperties</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Darcs1_0</span><span class='hs-layout'>,</span> <span class='hs-conid'>Darcs2</span><span class='hs-layout'>,</span> <span class='hs-conid'>HashedInventory</span><span class='hs-layout'>,</span> <span class='hs-conid'>NoWorkingDir</span><span class='hs-keyglyph'>]</span>
<a name="line-152"></a>
<a name="line-153"></a><a name="formatHas"></a><span class='hs-definition'>formatHas</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoProperty</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>RepoFormat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span>
<a name="line-154"></a><span class='hs-definition'>formatHas</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-conid'>RF</span> <span class='hs-varid'>ks</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>rp2ps</span> <span class='hs-varid'>f</span> <span class='hs-varop'>`elem`</span> <span class='hs-varid'>concat</span> <span class='hs-varid'>ks</span>
<a name="line-155"></a>
<a name="line-156"></a><a name="instance%20Show%20RepoProperty"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Show</span> <span class='hs-conid'>RepoProperty</span> <span class='hs-keyword'>where</span>
<a name="line-157"></a> <span class='hs-varid'>show</span> <span class='hs-conid'>Darcs1_0</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"darcs-1.0"</span>
<a name="line-158"></a> <span class='hs-varid'>show</span> <span class='hs-conid'>Darcs2</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"darcs-2"</span>
<a name="line-159"></a> <span class='hs-varid'>show</span> <span class='hs-conid'>HashedInventory</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"hashed"</span>
<a name="line-160"></a> <span class='hs-varid'>show</span> <span class='hs-conid'>NoWorkingDir</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"no-working-dir"</span>
<a name="line-161"></a><a name="rp2ps"></a><span class='hs-definition'>rp2ps</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>RepoProperty</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span>
<a name="line-162"></a><span class='hs-definition'>rp2ps</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BC</span><span class='hs-varop'>.</span><span class='hs-varid'>pack</span> <span class='hs-varop'>.</span> <span class='hs-varid'>show</span>
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