private Model SetModelSelectedItemInBackground(
Model model,
Func<Model, CompletionItem> selector)
{
if (model == null)
{
return null;
}
// Switch to hard selection.
var selectedItem = selector(model);
Contract.ThrowIfFalse(model.TotalItems.Contains(selectedItem) || model.DefaultBuilder == selectedItem);
if (model.FilteredItems.Contains(selectedItem))
{
// Easy case, just set the selected item that's already in the filtered items
// list.
return model.WithSelectedItem(selector(model))
.WithHardSelection(true);
}
else
{
// Item wasn't in the filtered list, so we need to recreate the filtered list
// with that item in it.
var filteredItemsSet = new HashSet<CompletionItem>(model.FilteredItems,
ReferenceEqualityComparer.Instance);
var newFilteredItems = model.TotalItems.Where(
i => filteredItemsSet.Contains(i) || i == selectedItem).ToList();
return model.WithFilteredItems(newFilteredItems)
.WithSelectedItem(selectedItem)
.WithHardSelection(true);
}
}
private static Model HandleAllItemsFilteredOut(
Model model,
CompletionFilterReason filterReason)
{
if (model.DismissIfEmpty &&
filterReason == CompletionFilterReason.Insertion)
{
// If the user was just typing, and the list went to empty *and* this is a
// language that wants to dismiss on empty, then just return a null model
// to stop the completion session.
return(null);
}
if (model.FilterState?.Values.Any(b => b) == true)
{
// If the user has turned on some filtering states, and we filtered down to
// nothing, then we do want the UI to show that to them. That way the user
// can turn off filters they don't want and get the right set of items.
return(model.WithFilteredItems(ImmutableArray <CompletionItem> .Empty)
.WithFilterText("")
.WithHardSelection(false)
.WithIsUnique(false));
}
else
{
// If we are going to filter everything out, then just preserve the existing
// model (and all the previously filtered items), but switch over to soft
// selection.
return(model.WithHardSelection(false)
.WithIsUnique(false));
}
}
private Model HandleDeletionTrigger(
Model model, CompletionFilterReason filterReason, List <FilterResult> filterResults)
{
if (filterReason == CompletionFilterReason.Insertion &&
!filterResults.Any(r => r.MatchedFilterText))
{
// The user has typed something, but nothing in the actual list matched what
// they were typing. In this case, we want to dismiss completion entirely.
// The thought process is as follows: we aggressively brough up completion
// to help them when they typed delete (in case they wanted to pick another
// item). However, they're typing something that doesn't seem to match at all
// The completion list is just distracting at this point.
return(null);
}
FilterResult?bestFilterResult = null;
int matchCount = 0;
foreach (var currentFilterResult in filterResults.Where(r => r.MatchedFilterText))
{
if (bestFilterResult == null ||
IsBetterDeletionMatch(currentFilterResult, bestFilterResult.Value))
{
// We had no best result yet, so this is now our best result.
bestFilterResult = currentFilterResult;
matchCount++;
}
}
// If we had a matching item, then pick the best of the matching items and
// choose that one to be hard selected. If we had no actual matching items
// (which can happen if the user deletes down to a single character and we
// include everything), then we just soft select the first item.
var filteredItems = filterResults.Select(r => r.CompletionItem).AsImmutable();
model = model.WithFilteredItems(filteredItems);
if (bestFilterResult != null)
{
// Only hard select this result if it's a prefix match
// We need to do this so that
// * deleting and retyping a dot in a member access does not change the
// text that originally appeared before the dot
// * deleting through a word from the end keeps that word selected
// This also preserves the behavior the VB had through Dev12.
var hardSelect = bestFilterResult.Value.CompletionItem.FilterText.StartsWith(model.FilterText, StringComparison.CurrentCultureIgnoreCase);
return(model.WithSelectedItem(bestFilterResult.Value.CompletionItem)
.WithHardSelection(hardSelect)
.WithIsUnique(matchCount == 1));
}
else
{
return(model.WithHardSelection(false)
.WithIsUnique(false));
}
}
private Model HandleNormalFiltering(
Model model,
Document document,
CompletionFilterReason filterReason,
ITextSnapshot textSnapshot,
CompletionHelper helper,
ImmutableArray <string> recentItems,
string filterText,
List <FilterResult> filterResults)
{
// Not deletion. Defer to the language to decide which item it thinks best
// matches the text typed so far.
// Ask the language to determine which of the *matched* items it wants to select.
var service = this.Controller.GetCompletionService();
if (service == null)
{
return(null);
}
var matchingCompletionItems = filterResults.Where(r => r.MatchedFilterText)
.Select(t => t.PresentationItem.Item)
.AsImmutable();
var chosenItems = service.FilterItems(
document, matchingCompletionItems, filterText);
// Of the items the service returned, pick the one most recently committed
var bestCompletionItem = GetBestCompletionItemBasedOnMRU(chosenItems, recentItems);
// If we don't have a best completion item yet, then pick the first item from the list.
var bestOrFirstCompletionItem = bestCompletionItem ?? filterResults.First().PresentationItem.Item;
var bestOrFirstPresentationItem = filterResults.Where(
r => r.PresentationItem.Item == bestOrFirstCompletionItem).First().PresentationItem;
var hardSelection = IsHardSelection(
model, bestOrFirstPresentationItem, textSnapshot, helper, filterReason);
// Determine if we should consider this item 'unique' or not. A unique item
// will be automatically committed if the user hits the 'invoke completion'
// without bringing up the completion list. An item is unique if it was the
// only item to match the text typed so far, and there was at least some text
// typed. i.e. if we have "Console.$$" we don't want to commit something
// like "WriteLine" since no filter text has actually been provided. HOwever,
// if "Console.WriteL$$" is typed, then we do want "WriteLine" to be committed.
var matchingItemCount = matchingCompletionItems.Length;
var isUnique = bestCompletionItem != null &&
matchingItemCount == 1 &&
filterText.Length > 0;
var result = model.WithFilteredItems(filterResults.Select(r => r.PresentationItem).AsImmutable())
.WithSelectedItem(bestOrFirstPresentationItem)
.WithHardSelection(hardSelection)
.WithIsUnique(isUnique);
return(result);
}
private Model HandleDeletionTrigger(
Model model, CompletionFilterReason filterReason, List <FilterResult> filterResults)
{
if (filterReason == CompletionFilterReason.Insertion &&
!filterResults.Any(r => r.MatchedFilterText))
{
// The user has typed something, but nothing in the actual list matched what
// they were typing. In this case, we want to dismiss completion entirely.
// The thought process is as follows: we aggressively brough up completion
// to help them when they typed delete (in case they wanted to pick another
// item). However, they're typing something that doesn't seem to match at all
// The completion list is just distracting at this point.
return(null);
}
FilterResult?bestFilterResult = null;
int matchCount = 0;
foreach (var currentFilterResult in filterResults.Where(r => r.MatchedFilterText))
{
if (bestFilterResult == null ||
IsBetterDeletionMatch(currentFilterResult, bestFilterResult.Value))
{
// We had no best result yet, so this is now our best result.
bestFilterResult = currentFilterResult;
matchCount++;
}
}
// If we had a matching item, then pick the best of the matching items and
// choose that one to be hard selected. If we had no actual matching items
// (which can happen if the user deletes down to a single character and we
// include everything), then we just soft select the first item.
var filteredItems = filterResults.Select(r => r.CompletionItem).AsImmutable();
model = model.WithFilteredItems(filteredItems);
if (bestFilterResult != null)
{
return(model.WithSelectedItem(bestFilterResult.Value.CompletionItem)
.WithHardSelection(true)
.WithIsUnique(matchCount == 1));
}
else
{
return(model.WithHardSelection(false)
.WithIsUnique(false));
}
}
private Model HandleDeletionTrigger(Model model, List <FilterResult> filterResults)
{
FilterResult?bestFilterResult = null;
int matchCount = 0;
foreach (var currentFilterResult in filterResults.Where(r => r.MatchedFilterText))
{
if (bestFilterResult == null ||
IsBetterDeletionMatch(currentFilterResult, bestFilterResult.Value))
{
// We had no best result yet, so this is now our best result.
bestFilterResult = currentFilterResult;
matchCount++;
}
}
// If we had a matching item, then pick the best of the matching items and
// choose that one to be hard selected. If we had no actual matching items
// (which can happen if the user deletes down to a single character and we
// include everything), then we just soft select the first item.
var filteredItems = filterResults.Select(r => r.CompletionItem).AsImmutable();
model = model.WithFilteredItems(filteredItems);
if (bestFilterResult != null)
{
return(model.WithSelectedItem(bestFilterResult.Value.CompletionItem)
.WithHardSelection(true)
.WithIsUnique(matchCount == 1));
}
else
{
return(model.WithHardSelection(false)
.WithIsUnique(false));
}
}
private Model SetModelSelectedItemInBackground(
Model model,
Func <Model, PresentationItem> selector)
{
if (model == null)
{
return(null);
}
// Switch to hard selection.
var selectedItem = selector(model);
Contract.ThrowIfFalse(model.TotalItems.Contains(selectedItem) || model.DefaultSuggestionModeItem == selectedItem);
if (model.FilteredItems.Contains(selectedItem))
{
// Easy case, just set the selected item that's already in the filtered items
// list.
return(model.WithSelectedItem(selector(model))
.WithHardSelection(true));
}
else
{
// Item wasn't in the filtered list, so we need to recreate the filtered list
// with that item in it.
var filteredItemsSet = new HashSet <PresentationItem>(model.FilteredItems,
ReferenceEqualityComparer.Instance);
var newFilteredItems = model.TotalItems.Where(
i => filteredItemsSet.Contains(i) || i == selectedItem).ToImmutableArrayOrEmpty();
return(model.WithFilteredItems(newFilteredItems)
.WithSelectedItem(selectedItem)
.WithHardSelection(true));
}
}
private Model FilterModelInBackgroundWorker(
Model model,
int id,
SnapshotPoint caretPosition,
bool recheckCaretPosition,
bool dismissIfEmptyAllowed,
CompletionFilterReason filterReason)
{
if (model == null)
{
return(null);
}
var filterState = model.FilterState;
// If all the filters are on, or all the filters are off then we don't actually
// need to filter.
if (filterState != null)
{
if (filterState.Values.All(b => b) ||
filterState.Values.All(b => !b))
{
filterState = null;
}
}
// We want to dismiss the session if the caret ever moved outside our bounds.
if (recheckCaretPosition && Controller.IsCaretOutsideAllItemBounds(model, caretPosition))
{
return(null);
}
if (id != _filterId)
{
return(model);
}
var textSnapshot = caretPosition.Snapshot;
var allFilteredItems = new List <PresentationItem>();
var textSpanToText = new Dictionary <TextSpan, string>();
var helper = this.Controller.GetCompletionHelper();
// isUnique tracks if there is a single
bool? isUnique = null;
PresentationItem bestFilterMatch = null;
bool filterTextIsPotentialIdentifier = false;
var recentItems = this.Controller.GetRecentItems();
var itemToFilterText = new Dictionary <CompletionItem, string>();
model = model.WithCompletionItemToFilterText(itemToFilterText);
foreach (var currentItem in model.TotalItems)
{
// Check if something new has happened and there's a later on filter operation
// in the chain. If so, there's no need for us to do any more work (as it will
// just be superceded by the later work).
if (id != _filterId)
{
return(model);
}
// We may have wrapped some items in the list in DescriptionModifying items,
// but we should use the actual underlying items when filtering. That way
// our rules can access the underlying item's provider.
if (ItemIsFilteredOut(currentItem.Item, filterState))
{
continue;
}
var filterText = model.GetCurrentTextInSnapshot(currentItem.Item.Span, textSnapshot, textSpanToText);
var matchesFilterText = helper.MatchesFilterText(currentItem.Item, filterText, model.Trigger, filterReason, recentItems);
itemToFilterText[currentItem.Item] = filterText;
if (matchesFilterText)
{
allFilteredItems.Add(currentItem);
// If we have no best match, or this match is better than the last match,
// then the current item is the best filter match.
if (bestFilterMatch == null ||
helper.IsBetterFilterMatch(currentItem.Item, bestFilterMatch.Item, filterText, model.Trigger, filterReason, recentItems))
{
bestFilterMatch = currentItem;
}
// If isUnique is null, then this is the first time we've seen an item that
// matches the filter text. That item is now considered unique. However, if
// isUnique is non-null, then this is the second (or third, or fourth, etc.)
// that a provider said to include. It's no longer unique.
//
// Note: We only want to do this if any filter text was actually provided.
// This is so we can handle the following cases properly:
//
// Console.WriteLi$$
//
// If they try to commit unique item there, we want to commit to
// "WriteLine". However, if they just have:
//
// Console.$$
//
// And they try to commit unique item, we won't commit something just
// because it was in the MRU list.
if (filterText != string.Empty)
{
isUnique = isUnique == null || false;
}
}
else
{
if (filterText.Length <= 1)
{
// Even though the rule provider didn't match this, we'll still include it
// since we want to allow a user typing a single character and seeing all
// possibly completions. However, we don't consider it either unique or a
// filter match, so we won't select it.
allFilteredItems.Add(currentItem);
}
// We want to dismiss the list if the user is typing a # and nothing matches
filterTextIsPotentialIdentifier = filterTextIsPotentialIdentifier ||
filterText.Length == 0 ||
(!char.IsDigit(filterText[0]) && filterText[0] != '-' && filterText[0] != '.');
}
}
if (!filterTextIsPotentialIdentifier && bestFilterMatch == null)
{
// We had no matches, and the user is typing a #, dismiss the list
return(null);
}
if (allFilteredItems.Count == 0)
{
if (dismissIfEmptyAllowed &&
model.DismissIfEmpty &&
filterReason != CompletionFilterReason.BackspaceOrDelete)
{
return(null);
}
if (model.FilterState != null && model.FilterState.Values.Any(b => b))
{
// If the user has turned on some filtering states, and we filtered down to
// nothing, then we do want the UI to show that to them.
return(model.WithFilteredItems(allFilteredItems.ToImmutableArray())
.WithHardSelection(false)
.WithIsUnique(false));
}
else
{
// If we are going to filter everything out, then just preserve the existing
// model, but switch over to soft selection. Also, nothing is unique at that
// point.
return(model.WithHardSelection(false)
.WithIsUnique(false));
}
}
// If we have a best item, then select it. Otherwise just use the first item
// in the list.
var selectedItem = bestFilterMatch ?? allFilteredItems.First();
// If we have a best item, then we want to hard select it. Otherwise we want
// soft selection. However, no hard selection if there's a builder.
var hardSelection = IsHardSelection(model, bestFilterMatch, textSnapshot, helper, model.Trigger, filterReason);
var result = model.WithFilteredItems(allFilteredItems.ToImmutableArray())
.WithSelectedItem(selectedItem)
.WithHardSelection(hardSelection)
.WithIsUnique(isUnique.HasValue && isUnique.Value);
return(result);
}
private Model FilterModelInBackgroundWorker(
Model model,
int id,
SnapshotPoint caretPosition,
bool recheckCaretPosition,
bool dismissIfEmptyAllowed,
CompletionFilterReason filterReason)
{
if (model == null)
{
return null;
}
var filterState = model.FilterState;
// If all the filters are on, or all the filters are off then we don't actually
// need to filter.
if (filterState != null)
{
if (filterState.Values.All(b => b) ||
filterState.Values.All(b => !b))
{
filterState = null;
}
}
// We want to dismiss the session if the caret ever moved outside our bounds.
if (recheckCaretPosition && Controller.IsCaretOutsideAllItemBounds(model, caretPosition))
{
return null;
}
if (id != _filterId)
{
return model;
}
var textSnapshot = caretPosition.Snapshot;
var allFilteredItems = new List<PresentationItem>();
var textSpanToText = new Dictionary<TextSpan, string>();
var helper = this.Controller.GetCompletionHelper();
// isUnique tracks if there is a single
bool? isUnique = null;
PresentationItem bestFilterMatch = null;
bool filterTextIsPotentialIdentifier = false;
var recentItems = this.Controller.GetRecentItems();
var itemToFilterText = new Dictionary<CompletionItem, string>();
model = model.WithCompletionItemToFilterText(itemToFilterText);
foreach (var currentItem in model.TotalItems)
{
// Check if something new has happened and there's a later on filter operation
// in the chain. If so, there's no need for us to do any more work (as it will
// just be superceded by the later work).
if (id != _filterId)
{
return model;
}
// We may have wrapped some items in the list in DescriptionModifying items,
// but we should use the actual underlying items when filtering. That way
// our rules can access the underlying item's provider.
if (ItemIsFilteredOut(currentItem.Item, filterState))
{
continue;
}
var filterText = model.GetCurrentTextInSnapshot(currentItem.Item.Span, textSnapshot, textSpanToText);
var matchesFilterText = MatchesFilterText(helper, currentItem.Item, filterText, model.Trigger, filterReason, recentItems);
itemToFilterText[currentItem.Item] = filterText;
if (matchesFilterText)
{
allFilteredItems.Add(currentItem);
// If we have no best match, or this match is better than the last match,
// then the current item is the best filter match.
if (bestFilterMatch == null ||
IsBetterFilterMatch(helper, currentItem.Item, bestFilterMatch.Item, filterText, model.Trigger, filterReason, recentItems))
{
bestFilterMatch = currentItem;
}
// If isUnique is null, then this is the first time we've seen an item that
// matches the filter text. That item is now considered unique. However, if
// isUnique is non-null, then this is the second (or third, or fourth, etc.)
// that a provider said to include. It's no longer unique.
//
// Note: We only want to do this if any filter text was actually provided.
// This is so we can handle the following cases properly:
//
// Console.WriteLi$$
//
// If they try to commit unique item there, we want to commit to
// "WriteLine". However, if they just have:
//
// Console.$$
//
// And they try to commit unique item, we won't commit something just
// because it was in the MRU list.
if (filterText != string.Empty)
{
isUnique = isUnique == null || false;
}
}
else
{
if (filterText.Length <= 1)
{
// Even though the rule provider didn't match this, we'll still include it
// since we want to allow a user typing a single character and seeing all
// possibly completions. However, we don't consider it either unique or a
// filter match, so we won't select it.
allFilteredItems.Add(currentItem);
}
// We want to dismiss the list if the user is typing a # and nothing matches
filterTextIsPotentialIdentifier = filterTextIsPotentialIdentifier ||
filterText.Length == 0 ||
(!char.IsDigit(filterText[0]) && filterText[0] != '-' && filterText[0] != '.');
}
}
if (!filterTextIsPotentialIdentifier && bestFilterMatch == null)
{
// We had no matches, and the user is typing a #, dismiss the list
return null;
}
if (allFilteredItems.Count == 0)
{
if (dismissIfEmptyAllowed &&
model.DismissIfEmpty &&
filterReason != CompletionFilterReason.BackspaceOrDelete)
{
return null;
}
if (model.FilterState != null && model.FilterState.Values.Any(b => b))
{
// If the user has turned on some filtering states, and we filtered down to
// nothing, then we do want the UI to show that to them.
return model.WithFilteredItems(allFilteredItems.ToImmutableArray())
.WithHardSelection(false)
.WithIsUnique(false);
}
else
{
// If we are going to filter everything out, then just preserve the existing
// model, but switch over to soft selection. Also, nothing is unique at that
// point.
return model.WithHardSelection(false)
.WithIsUnique(false);
}
}
// If we have a best item, then select it. Otherwise just use the first item
// in the list.
var selectedItem = bestFilterMatch ?? allFilteredItems.First();
// If we have a best item, then we want to hard select it. Otherwise we want
// soft selection. However, no hard selection if there's a builder.
var hardSelection = IsHardSelection(model, bestFilterMatch, textSnapshot, helper, model.Trigger, filterReason);
var result = model.WithFilteredItems(allFilteredItems.ToImmutableArray())
.WithSelectedItem(selectedItem)
.WithHardSelection(hardSelection)
.WithIsUnique(isUnique.HasValue && isUnique.Value);
return result;
}
private static Model HandleAllItemsFilteredOut(
Model model,
CompletionFilterReason filterReason,
bool dismissIfEmptyAllowed)
{
if (dismissIfEmptyAllowed &&
model.DismissIfEmpty &&
filterReason == CompletionFilterReason.TypeChar)
{
// If the user was just typing, and the list went to empty *and* this is a
// language that wants to dismiss on empty, then just return a null model
// to stop the completion session.
return null;
}
if (model.FilterState?.Values.Any(b => b) == true)
{
// If the user has turned on some filtering states, and we filtered down to
// nothing, then we do want the UI to show that to them. That way the user
// can turn off filters they don't want and get the right set of items.
return model.WithFilteredItems(ImmutableArray<PresentationItem>.Empty)
.WithFilterText("")
.WithHardSelection(false)
.WithIsUnique(false);
}
else
{
// If we are going to filter everything out, then just preserve the existing
// model (and all the previously filtered items), but switch over to soft
// selection.
return model.WithHardSelection(false)
.WithIsUnique(false);
}
}
private Model HandleDeletionTrigger(Model model, List<FilterResult> filterResults)
{
FilterResult? bestFilterResult = null;
int matchCount = 0;
foreach (var currentFilterResult in filterResults.Where(r => r.MatchedFilterText))
{
if (bestFilterResult == null ||
IsBetterDeletionMatch(currentFilterResult, bestFilterResult.Value))
{
// We had no best result yet, so this is now our best result.
bestFilterResult = currentFilterResult;
matchCount++;
}
}
// If we had a matching item, then pick the best of the matching items and
// choose that one to be hard selected. If we had no actual matching items
// (which can happen if the user deletes down to a single character and we
// include everything), then we just soft select the first item.
var filteredItems = filterResults.Select(r => r.PresentationItem).AsImmutable();
model = model.WithFilteredItems(filteredItems);
if (bestFilterResult != null)
{
return model.WithSelectedItem(bestFilterResult.Value.PresentationItem)
.WithHardSelection(true)
.WithIsUnique(matchCount == 1);
}
else
{
return model.WithHardSelection(false)
.WithIsUnique(false);
}
}
private Model HandleNormalFiltering(
Model model, CompletionFilterReason filterReason,
ITextSnapshot textSnapshot, Document document,
CompletionHelper helper, ImmutableArray<string> recentItems,
string filterText,
List<FilterResult> filterResults)
{
// Not deletion. Defer to the language to decide which item it thinks best
// matches the text typed so far.
// Ask the language to determine which of the *matched* items it wants to select.
var service = this.Controller.GetCompletionService();
var matchingCompletionItems = filterResults.Where(r => r.MatchedFilterText)
.Select(t => t.PresentationItem.Item)
.AsImmutable();
var chosenItems = service.ChooseBestItems(document, matchingCompletionItems, filterText);
// Of the items the service returned, pick the one most recently committed
var bestCompletionItem = GetBestCompletionItemBasedOnMRU(chosenItems, recentItems);
// If we don't have a best completion item yet, then pick the first item from the list.
var bestOrFirstCompletionItem = bestCompletionItem ?? filterResults.First().PresentationItem.Item;
var bestOrFirstPresentationItem = filterResults.Where(
r => r.PresentationItem.Item == bestOrFirstCompletionItem).First().PresentationItem;
var hardSelection = IsHardSelection(
model, bestOrFirstPresentationItem, textSnapshot, helper, filterReason);
// Determine if we should consider this item 'unique' or not. A unique item
// will be automatically committed if the user hits the 'invoke completion'
// without bringing up the completion list. An item is unique if it was the
// only item to match the text typed so far, and there was at least some text
// typed. i.e. if we have "Console.$$" we don't want to commit something
// like "WriteLine" since no filter text has actually been provided. HOwever,
// if "Console.WriteL$$" is typed, then we do want "WriteLine" to be committed.
var matchingItemCount = matchingCompletionItems.Length;
var isUnique = bestCompletionItem != null &&
matchingItemCount == 1 &&
filterText.Length > 0;
var result = model.WithFilteredItems(filterResults.Select(r => r.PresentationItem).AsImmutable())
.WithSelectedItem(bestOrFirstPresentationItem)
.WithHardSelection(hardSelection)
.WithIsUnique(isUnique);
return result;
}