lumiera_documentation/tests/lib/iter-chain-search-test.cpp
Ichthyostega 3caa5cfb03 Tests: reorganise test folders
This resolves a long-standing issue:
we could not use proper include paths for test-helper code that was defined alongside the tests.

Since some test-helper code must now be relocated into the »Vault«-Layer,
I took the opportunity to finally resolve this annoyance. The solution is two-fold
 * introduce a dedicated test-support library
 * remove the quirks that were necessary to support some plain-C tests
Together, this allows to raise the include-directory by one level,
and then to adjust all folder names so that they match the namespace
2026-03-07 00:56:19 +01:00

216 lines
8.7 KiB
C++
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
IterChainSearch(Test) - verify chained search operations with backtracking
Copyright (C)
2018, Hermann Vosseler <Ichthyostega@web.de>
  **Lumiera** is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by the
  Free Software Foundation; either version 2 of the License, or (at your
  option) any later version. See the file COPYING for further details.
* *****************************************************************/
/** @file iter-chain-search-test.cpp
** unit test \ref IterChainSearch_test
*/
#include "test/run.hpp"
#include "test/test-helper.hpp"
#include "lib/format-util.hpp"
#include "lib/iter-chain-search.hpp"
#include "lib/iter-cursor.hpp"
#include "lib/util.hpp"
#include <vector>
#include <string>
namespace lib {
namespace iter{
namespace test{
using ::Test;
using util::join;
using util::isnil;
using util::startsWith;
using util::isSameObject;
using std::vector;
using std::string;
using LERR_(ITER_EXHAUST);
namespace { // test fixture
using Spam = vector<string>;
const Spam SPAM{"spam"
,"sausage"
,"spam"
,"spam"
,"bacon"
,"spam"
,"tomato"
,"and"
,"spam"
};
/** Diagnostic helper: join all the elements from a _copy_ of the iterator */
template<class II>
inline string
materialise (II&& ii)
{
return util::join (std::forward<II> (ii), "-");
}
}// (END)fixture
/*****************************************************************//**
* @test verify a setup for consecutive searches with backtracking.
* - demonstrate simple consecutive matches and iterator behaviour
* - clear the filter underway and thus return to simple iteration
* - set up two conditions, the second one capturing state at the
* point where the first one matches
* - wrap a lib::IterCursor, which allows to toggle the search
* direction underway; this creates a situation where the
* first options picked do not lead to a successful solution,
* so the search has to track back, try further options and
* in each case re-apply all the following consecutive
* search conditions.
*
* @see iter-chain-search.hpp
* @see iter-cursor.hpp
* @see [usage example](\ref event-log.hpp)
*/
class IterChainSearch_test : public Test
{
virtual void
run (Arg)
{
simpleSearch();
chainedIteration();
backtracking();
}
/** @test simple basic use case. */
void
simpleSearch ()
{
auto search = chainSearch(SPAM)
.search("bacon")
.search("tomato");
CHECK (search);
CHECK (not isnil(search));
CHECK ("tomato" == *search);
CHECK (isSameObject (*search, SPAM[6]));
search.clearFilter();
CHECK ("tomato" == *search);
++search;
CHECK ("and" == *search);
search.search("spam");
CHECK ("spam" == *search);
CHECK (isSameObject (*search, SPAM[8]));
++search;
CHECK (not search);
CHECK (isnil (search));
VERIFY_ERROR (ITER_EXHAUST, *search);
}
/** @test verify consecutive application of several functors on the underlying filter.
* In the general case, each step in the chain is a function working on a copy of the
* current filter state. Since each such step configures its own copy of the complete
* pipeline, it may reconfigure this filter pipeline in arbitrary ways. After exhausting
* the last layer, the evaluation returns to the previous layer, but immediately re-applies
* the configuration step on the then next element.
*/
void
chainedIteration ()
{
auto search = chainSearch(SPAM) // Note: 1st filter step picks all s-words
.search([](string const& str){ return startsWith (str, "s"); });
CHECK (materialise (search) =="spam-sausage-spam-spam-spam-spam");
CHECK ("spam" == *search);
search.addStep([](auto& filter)
{ // Note: pick the current value at the point
string currVal = *filter; // where the 2nd filter step is (re)applied
filter.setNewFilter ([=](string const& val) // ...and bake this value into the lambda closure
{
return val != currVal;
});
});
CHECK ("sausage" == *search);
CHECK (materialise (search)
== "sausage-bacon-tomato-and-" // everything in the rest, which is not "spam"
"spam-spam-bacon-spam-tomato-and-spam-" // everything starting at "sausage" which is not "sausage"
"bacon-tomato-and-" // any non-spam behind the 2nd spam
"bacon-tomato-and-" // any non-spam behind the 3rd spam
"tomato-and" // any non-spam behind the 4th spam
""); // and any non-spam behind the final spam
}
/** @test verify a complex search with backtracking.
* This becomes relevant when a given search condition can be "too greedy" for the
* complete chain to succeed. Most notably this is the case when the search is fundamentally
* reconfigured in some steps, e.g. by switching the search orientation. To demonstrate this,
* we use a "gear switching" iterator, which allows us to reverse the direction and to search
* backwards from the current position. We configure the second condition in the chain such
* that it can not succeed when starting from the first match on the first condition
*/
void
backtracking ()
{
using Cursor = IterCursor<decltype(SPAM.begin())>;
auto search = chainSearch(Cursor{SPAM.begin(), SPAM.end()})
.search("spam")
.addStep([](auto& filter)
{
filter.switchBackwards(); // switch search direction without moving the cursor
filter.flipFilter(); // flip from match on "spam" to match on non-spam
})
.addStep([](auto& filter)
{ // filter is still configured to search non-spam backwards
++filter; // just "advance" this filter by one step (backward)
});
CHECK (materialise (search) // Layer-0: 1-3 spam fail altogether, too greedy. Try 4rd spam....
// Layer-1: turn back, toggle to non-spam, find bacon
== "sausage-" // Layer-2: non-spam and one step further backwards yields sausage
//
// BACKTRACK to Layer-0: pick 5th (and last) spam...
// Layer-1: turn back, toggle to non-spam, find "and"
"tomato-bacon-sausage-" // Layer-2: non-spam and one step back yields tomato, next bacon, next sausage.
// BACKTRACK to Layer-1: take previous one, which is tomato
"bacon-sausage-" // Layer-2: non-spam and one step further back yields bacon, then next sausage.
// BACKTRACK to Layer-1: take previous non-spam, which is bacon
"sausage" // Layer-2: non-spam and one step further back yields sausage.
""); // BACKTRACK to Layer-1: exhausted, BACKTRACK to Layer-0: exhausted. Done.
}
};
LAUNCHER (IterChainSearch_test, "unit common");
}}} // namespace lib::iter::test