private IReadOnlyList <DocumentSnapshot> GetImportsCore(DefaultProjectSnapshot project)
{
var projectEngine = project.GetProjectEngine();
var importFeatures = projectEngine.ProjectFeatures.OfType <IImportProjectFeature>();
var projectItem = projectEngine.FileSystem.GetItem(HostDocument.FilePath, HostDocument.FileKind);
var importItems = importFeatures.SelectMany(f => f.GetImports(projectItem));
if (importItems == null)
{
return(Array.Empty <DocumentSnapshot>());
}
var imports = new List <DocumentSnapshot>();
foreach (var item in importItems)
{
if (item.PhysicalPath == null)
{
// This is a default import.
var defaultImport = new DefaultImportDocumentSnapshot(project, item);
imports.Add(defaultImport);
}
else
{
var import = project.GetDocument(item.PhysicalPath);
if (import == null)
{
// We are not tracking this document in this project. So do nothing.
continue;
}
imports.Add(import);
}
}
return(imports);
}
private async Task <(RazorCodeDocument, VersionStamp, VersionStamp, VersionStamp)> GetGeneratedOutputAndVersionCoreAsync(DefaultProjectSnapshot project, DocumentSnapshot document)
{
// We only need to produce the generated code if any of our inputs is newer than the
// previously cached output.
//
// First find the versions that are the inputs:
// - The project + computed state
// - The imports
// - This document
//
// All of these things are cached, so no work is wasted if we do need to generate the code.
var configurationVersion = project.State.ConfigurationVersion;
var projectWorkspaceStateVersion = project.State.ProjectWorkspaceStateVersion;
var documentCollectionVersion = project.State.DocumentCollectionVersion;
var imports = await GetImportsAsync(project, document).ConfigureAwait(false);
var documentVersion = await document.GetTextVersionAsync().ConfigureAwait(false);
// OK now that have the previous output and all of the versions, we can see if anything
// has changed that would require regenerating the code.
var inputVersion = documentVersion;
if (inputVersion.GetNewerVersion(configurationVersion) == configurationVersion)
{
inputVersion = configurationVersion;
}
if (inputVersion.GetNewerVersion(projectWorkspaceStateVersion) == projectWorkspaceStateVersion)
{
inputVersion = projectWorkspaceStateVersion;
}
if (inputVersion.GetNewerVersion(documentCollectionVersion) == documentCollectionVersion)
{
inputVersion = documentCollectionVersion;
}
for (var i = 0; i < imports.Count; i++)
{
var importVersion = imports[i].Version;
if (inputVersion.GetNewerVersion(importVersion) == importVersion)
{
inputVersion = importVersion;
}
}
RazorCodeDocument olderOutput = null;
var olderInputVersion = default(VersionStamp);
var olderCSharpOutputVersion = default(VersionStamp);
var olderHtmlOutputVersion = default(VersionStamp);
if (_older?.TaskUnsafeReference != null &&
_older.TaskUnsafeReference.TryGetTarget(out var taskUnsafe))
{
(olderOutput, olderInputVersion, olderCSharpOutputVersion, olderHtmlOutputVersion) = await taskUnsafe.ConfigureAwait(false);
if (inputVersion.GetNewerVersion(olderInputVersion) == olderInputVersion)
{
// Nothing has changed, we can use the cached result.
lock (_lock)
{
TaskUnsafeReference = _older.TaskUnsafeReference;
_older = null;
return(olderOutput, olderInputVersion, olderCSharpOutputVersion, olderHtmlOutputVersion);
}
}
}
// OK we have to generate the code.
var importSources = new List <RazorSourceDocument>();
var projectEngine = project.GetProjectEngine();
foreach (var item in imports)
{
var importProjectItem = item.FilePath == null ? null : projectEngine.FileSystem.GetItem(item.FilePath, item.FileKind);
var sourceDocument = await GetRazorSourceDocumentAsync(item.Document, importProjectItem).ConfigureAwait(false);
importSources.Add(sourceDocument);
}
var projectItem = document.FilePath == null ? null : projectEngine.FileSystem.GetItem(document.FilePath, document.FileKind);
var documentSource = await GetRazorSourceDocumentAsync(document, projectItem).ConfigureAwait(false);
var codeDocument = projectEngine.ProcessDesignTime(documentSource, fileKind: document.FileKind, importSources, project.TagHelpers);
var csharpDocument = codeDocument.GetCSharpDocument();
var htmlDocument = codeDocument.GetHtmlDocument();
// OK now we've generated the code. Let's check if the output is actually different. This is
// a valuable optimization for our use cases because lots of changes you could make require
// us to run code generation, but don't change the result.
//
// Note that we're talking about the effect on the generated C#/HTML here (not the other artifacts).
// This is the reason why we have three versions associated with the document.
//
// The INPUT version is related the .cshtml files and tag helpers
// The CSHARPOUTPUT version is related to the generated C#
// The HTMLOUTPUT version is related to the generated HTML
//
// Examples:
//
// A change to a tag helper not used by this document - updates the INPUT version, but not
// the OUTPUT version.
//
//
// Razor IDE features should always retrieve the output and party on it regardless. Depending
// on the use cases we may or may not need to synchronize the output.
var outputCSharpVersion = inputVersion;
var outputHtmlVersion = inputVersion;
if (olderOutput != null)
{
if (string.Equals(
olderOutput.GetCSharpDocument().GeneratedCode,
csharpDocument.GeneratedCode,
StringComparison.Ordinal))
{
outputCSharpVersion = olderCSharpOutputVersion;
}
if (string.Equals(
olderOutput.GetHtmlDocument().GeneratedHtml,
htmlDocument.GeneratedHtml,
StringComparison.Ordinal))
{
outputHtmlVersion = olderHtmlOutputVersion;
}
}
if (document is DefaultDocumentSnapshot defaultDocument)
{
defaultDocument.State.HostDocument.GeneratedDocumentContainer.SetOutput(
defaultDocument,
csharpDocument,
htmlDocument,
inputVersion,
outputCSharpVersion,
outputHtmlVersion);
}
return(codeDocument, inputVersion, outputCSharpVersion, outputHtmlVersion);
}