TextEditor: Make threshold for automatic completion configurable

Fixes: QTCREATORBUG-19920
Change-Id: Id6be79485b1fb8c2ab4cce2706816949ae5e217b
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangcodemodel/clangcompletionassistprocessor.cpp

@@ -43,6 +43,7 @@
 #include <texteditor/codeassist/functionhintproposal.h>
 #include <texteditor/codeassist/genericproposal.h>
 #include <texteditor/codeassist/ifunctionhintproposalmodel.h>
+#include <texteditor/texteditorsettings.h>
 
 #include <cplusplus/BackwardsScanner.h>
 #include <cplusplus/ExpressionUnderCursor.h>
@@ -405,11 +406,11 @@ bool ClangCompletionAssistProcessor::accepts() const
 
         return true;
     } else {
-        // Trigger completion after three characters of a name have been typed, when not editing an existing name
+        // Trigger completion after n characters of a name have been typed, when not editing an existing name
         QChar characterUnderCursor = m_interface->characterAt(pos);
         if (!characterUnderCursor.isLetterOrNumber() && characterUnderCursor != QLatin1Char('_')) {
             const int startOfName = findStartOfName(pos);
-            if (pos - startOfName >= 3) {
+            if (pos - startOfName >= TextEditorSettings::completionSettings().m_characterThreshold) {
                 const QChar firstCharacter = m_interface->characterAt(startOfName);
                 if (firstCharacter.isLetter() || firstCharacter == QLatin1Char('_')) {
                     // Finally check that we're not inside a comment or string (code copied from startOfOperator)

src/plugins/cpptools/cppcompletionassist.cpp

@@ -851,12 +851,12 @@ bool InternalCppCompletionAssistProcessor::accepts() const
 
         return true;
     } else {
-        // Trigger completion after three characters of a name have been typed, when not editing an existing name
+        // Trigger completion after n characters of a name have been typed, when not editing an existing name
         QChar characterUnderCursor = m_interface->characterAt(pos);
 
         if (!isValidIdentifierChar(characterUnderCursor)) {
             const int startOfName = findStartOfName(pos);
-            if (pos - startOfName >= 3) {
+            if (pos - startOfName >= TextEditorSettings::completionSettings().m_characterThreshold) {
                 const QChar firstCharacter = m_interface->characterAt(startOfName);
                 if (isValidFirstIdentifierChar(firstCharacter)) {
                     // Finally check that we're not inside a comment or string (code copied from startOfOperator)

src/plugins/glsleditor/glslcompletionassist.cpp

@@ -40,6 +40,7 @@
 #include <texteditor/codeassist/genericproposalmodel.h>
 #include <texteditor/codeassist/genericproposal.h>
 #include <texteditor/codeassist/functionhintproposal.h>
+#include <texteditor/texteditorsettings.h>
 #include <cplusplus/ExpressionUnderCursor.h>
 #include <cplusplus/Icons.h>
 
@@ -528,7 +529,8 @@ bool GlslCompletionAssistProcessor::acceptsIdleEditor() const
         ++pos;
 
         const QString word = m_interface->textAt(pos, cursorPosition - pos);
-        if (word.length() > 2 && checkStartOfIdentifier(word)) {
+        if (word.length() >= TextEditorSettings::completionSettings().m_characterThreshold
+                && checkStartOfIdentifier(word)) {
             for (auto character : word) {
                 if (!isIdentifierChar(character))
                     return false;

src/plugins/languageclient/languageclientcompletionassist.cpp

@@ -34,6 +34,7 @@
 #include <texteditor/codeassist/iassistprocessor.h>
 #include <texteditor/codeassist/genericproposal.h>
 #include <texteditor/codeassist/genericproposalmodel.h>
+#include <texteditor/texteditorsettings.h>
 #include <utils/algorithm.h>
 #include <utils/textutils.h>
 #include <utils/utilsicons.h>
@@ -314,13 +315,13 @@ IAssistProposal *LanguageClientCompletionAssistProcessor::perform(const AssistIn
     QTC_ASSERT(m_client, return nullptr);
     m_pos = interface->position();
     if (interface->reason() == IdleEditor) {
-        // Trigger an automatic completion request only when we are on a word with more than 2 "identifier" character
+        // Trigger an automatic completion request only when we are on a word with at least n "identifier" characters
         const QRegularExpression regexp("[_a-zA-Z0-9]+");
         auto hasMatch = [&regexp](const QString &txt) { return regexp.match(txt).hasMatch(); };
         int delta = 0;
         while (m_pos - delta > 0 && hasMatch(interface->textAt(m_pos - delta - 1, delta + 1)))
             ++delta;
-        if (delta < 3)
+        if (delta < TextEditorSettings::completionSettings().m_characterThreshold)
             return nullptr;
         if (m_client->documentUpdatePostponed(interface->fileName())) {
             m_postponedUpdateConnection

src/plugins/qmljseditor/qmljscompletionassist.cpp

@@ -891,7 +891,8 @@ bool QmlJSCompletionAssistProcessor::acceptsIdleEditor() const
             ++startPos;
 
             const QString &word = m_interface->textAt(startPos, cursorPos - startPos);
-            if (word.length() > 2 && isIdentifierChar(word.at(0), true)) {
+            if (word.length() >= TextEditorSettings::completionSettings().m_characterThreshold
+                    && isIdentifierChar(word.at(0), true)) {
                 for (int i = 1; i < word.length(); ++i) {
                     if (!isIdentifierChar(word.at(i)))
                         return false;

src/plugins/texteditor/codeassist/documentcontentcompletion.cpp

@@ -31,6 +31,8 @@
 #include "genericproposalmodel.h"
 #include "iassistprocessor.h"
 #include "../snippets/snippetassistcollector.h"
+#include "../completionsettings.h"
+#include "../texteditorsettings.h"
 
 #include <utils/algorithm.h>
 #include <utils/runextensions.h>
@@ -127,9 +129,11 @@ IAssistProposal *DocumentContentCompletionProcessor::perform(const AssistInterfa
 
     if (interface->reason() == IdleEditor) {
         QChar characterUnderCursor = interface->characterAt(interface->position());
-        if (characterUnderCursor.isLetterOrNumber() || length < 3)
+        if (characterUnderCursor.isLetterOrNumber()
+                || length < TextEditorSettings::completionSettings().m_characterThreshold) {
             return nullptr;
         }
+    }
 
     const QString wordUnderCursor = interface->textAt(pos, length);
     const QString text = interface->textDocument()->toPlainText();

src/plugins/texteditor/codeassist/keywordscompletionassist.cpp

@@ -195,7 +195,8 @@ IAssistProposal *KeywordsCompletionAssistProcessor::perform(const AssistInterfac
 
     if (interface->reason() == IdleEditor) {
         QChar characterUnderCursor = interface->characterAt(interface->position());
-        if (characterUnderCursor.isLetterOrNumber() || interface->position() - startPosition < 3) {
+        if (characterUnderCursor.isLetterOrNumber() || interface->position() - startPosition
+                < TextEditorSettings::completionSettings().m_characterThreshold) {
             QList<AssistProposalItemInterface *> items;
             if (m_dynamicCompletionFunction)
                 m_dynamicCompletionFunction(interface, &items, startPosition);

src/plugins/texteditor/completionsettings.cpp

@@ -31,6 +31,7 @@ static const char settingsGroup[]               = "CppTools/Completion";
 static const char caseSensitivityKey[]          = "CaseSensitivity";
 static const char completionTriggerKey[]        = "CompletionTrigger";
 static const char automaticProposalTimeoutKey[] = "AutomaticProposalTimeout";
+static const char characterThresholdKey[]       = "CharacterThreshold";
 static const char autoInsertBracesKey[]         = "AutoInsertBraces";
 static const char surroundingAutoBracketsKey[]  = "SurroundingAutoBrackets";
 static const char autoInsertQuotesKey[]         = "AutoInsertQuotes";
@@ -52,6 +53,7 @@ void CompletionSettings::toSettings(QSettings *s) const
     s->setValue(caseSensitivityKey, (int) m_caseSensitivity);
     s->setValue(completionTriggerKey, (int) m_completionTrigger);
     s->setValue(automaticProposalTimeoutKey, m_automaticProposalTimeoutInMs);
+    s->setValue(characterThresholdKey, m_characterThreshold);
     s->setValue(autoInsertBracesKey, m_autoInsertBrackets);
     s->setValue(surroundingAutoBracketsKey, m_surroundingAutoBrackets);
     s->setValue(autoInsertQuotesKey, m_autoInsertQuotes);
@@ -78,6 +80,8 @@ void CompletionSettings::fromSettings(QSettings *s)
             s->value(completionTriggerKey, m_completionTrigger).toInt();
     m_automaticProposalTimeoutInMs =
             s->value(automaticProposalTimeoutKey, m_automaticProposalTimeoutInMs).toInt();
+    m_characterThreshold =
+            s->value(characterThresholdKey, m_characterThreshold).toInt();
     m_autoInsertBrackets =
             s->value(autoInsertBracesKey, m_autoInsertBrackets).toBool();
     m_surroundingAutoBrackets =
@@ -110,6 +114,7 @@ bool CompletionSettings::equals(const CompletionSettings &cs) const
     return m_caseSensitivity                == cs.m_caseSensitivity
         && m_completionTrigger              == cs.m_completionTrigger
         && m_automaticProposalTimeoutInMs   == cs.m_automaticProposalTimeoutInMs
+        && m_characterThreshold             == cs.m_characterThreshold
         && m_autoInsertBrackets             == cs.m_autoInsertBrackets
         && m_surroundingAutoBrackets        == cs.m_surroundingAutoBrackets
         && m_autoInsertQuotes               == cs.m_autoInsertQuotes

src/plugins/texteditor/completionsettings.h

@@ -59,6 +59,7 @@ public:
     CaseSensitivity m_caseSensitivity = CaseInsensitive;
     CompletionTrigger m_completionTrigger = AutomaticCompletion;
     int m_automaticProposalTimeoutInMs = 400;
+    int m_characterThreshold = 3;
     bool m_autoInsertBrackets = true;
     bool m_surroundingAutoBrackets = true;
     bool m_autoInsertQuotes = true;

src/plugins/texteditor/completionsettingspage.cpp

@@ -100,6 +100,7 @@ CompletionSettingsPageWidget::CompletionSettingsPageWidget(CompletionSettingsPag
     m_ui.completionTrigger->setCurrentIndex(completionTriggerIndex);
     m_ui.automaticProposalTimeoutSpinBox
             ->setValue(m_owner->m_completionSettings.m_automaticProposalTimeoutInMs);
+    m_ui.thresholdSpinBox->setValue(m_owner->m_completionSettings.m_characterThreshold);
     m_ui.insertBrackets->setChecked(m_owner->m_completionSettings.m_autoInsertBrackets);
     m_ui.surroundBrackets->setChecked(m_owner->m_completionSettings.m_surroundingAutoBrackets);
     m_ui.insertQuotes->setChecked(m_owner->m_completionSettings.m_autoInsertQuotes);
@@ -173,6 +174,7 @@ void CompletionSettingsPageWidget::settingsFromUi(CompletionSettings &completion
     completion.m_completionTrigger = completionTrigger();
     completion.m_automaticProposalTimeoutInMs
             = m_ui.automaticProposalTimeoutSpinBox->value();
+    completion.m_characterThreshold = m_ui.thresholdSpinBox->value();
     completion.m_autoInsertBrackets = m_ui.insertBrackets->isChecked();
     completion.m_surroundingAutoBrackets = m_ui.surroundBrackets->isChecked();
     completion.m_autoInsertQuotes = m_ui.insertQuotes->isChecked();

src/plugins/texteditor/completionsettingspage.ui

@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>551</width>
-    <height>507</height>
+    <width>823</width>
+    <height>756</height>
    </rect>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout_2">
@@ -16,27 +16,9 @@
      <property name="title">
       <string>Behavior</string>
      </property>
-     <layout class="QGridLayout" name="gridLayout">
-      <item row="1" column="0">
-       <widget class="QLabel" name="completionTriggerLabel">
-        <property name="text">
-         <string>Activate completion:</string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="2" colspan="4">
-       <spacer name="horizontalSpacer">
-        <property name="orientation">
-         <enum>Qt::Horizontal</enum>
-        </property>
-        <property name="sizeHint" stdset="0">
-         <size>
-          <width>70</width>
-          <height>24</height>
-         </size>
-        </property>
-       </spacer>
-      </item>
+     <layout class="QVBoxLayout" name="verticalLayout_3">
+      <item>
+       <layout class="QFormLayout" name="formLayout">
         <item row="0" column="0">
          <widget class="QLabel" name="caseSensitivityLabel">
           <property name="text">
@@ -48,6 +30,8 @@
          </widget>
         </item>
         <item row="0" column="1">
+         <layout class="QHBoxLayout" name="horizontalLayout">
+          <item>
            <widget class="QComboBox" name="caseSensitivity">
             <property name="sizePolicy">
              <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
@@ -72,7 +56,31 @@
             </item>
            </widget>
           </item>
-      <item row="1" column="1" colspan="2">
+          <item>
+           <spacer name="horizontalSpacer">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </item>
+        <item row="1" column="0">
+         <widget class="QLabel" name="completionTriggerLabel">
+          <property name="text">
+           <string>Activate completion:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="1" column="1">
+         <layout class="QHBoxLayout" name="horizontalLayout_2">
+          <item>
            <widget class="QComboBox" name="completionTrigger">
             <item>
              <property name="text">
@@ -91,14 +99,31 @@
             </item>
            </widget>
           </item>
-      <item row="1" column="3">
+          <item>
+           <spacer name="horizontalSpacer_2">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </item>
+        <item row="2" column="0">
          <widget class="QLabel" name="automaticProposalTimeoutLabel">
           <property name="text">
            <string>Timeout in ms:</string>
           </property>
          </widget>
         </item>
-      <item row="1" column="4">
+        <item row="2" column="1">
+         <layout class="QHBoxLayout" name="horizontalLayout_7">
+          <item>
            <widget class="QSpinBox" name="automaticProposalTimeoutSpinBox">
             <property name="maximum">
              <number>2000</number>
@@ -111,7 +136,7 @@
             </property>
            </widget>
           </item>
-      <item row="1" column="5">
+          <item>
            <spacer name="horizontalSpacer_3">
             <property name="orientation">
              <enum>Qt::Horizontal</enum>
@@ -119,12 +144,45 @@
             <property name="sizeHint" stdset="0">
              <size>
               <width>40</width>
-          <height>24</height>
+              <height>20</height>
              </size>
             </property>
            </spacer>
           </item>
-      <item row="2" column="0">
+         </layout>
+        </item>
+        <item row="3" column="0">
+         <widget class="QLabel" name="thresholdLabel">
+          <property name="text">
+           <string>Character threshold:</string>
+          </property>
+         </widget>
+        </item>
+        <item row="3" column="1">
+         <layout class="QHBoxLayout" name="horizontalLayout_6">
+          <item>
+           <widget class="QSpinBox" name="thresholdSpinBox">
+            <property name="minimum">
+             <number>1</number>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <spacer name="horizontalSpacer_4">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </item>
+        <item row="4" column="0">
          <widget class="QCheckBox" name="partiallyComplete">
           <property name="toolTip">
            <string>Inserts the common prefix of available completion items.</string>
@@ -137,7 +195,7 @@
           </property>
          </widget>
         </item>
-      <item row="3" column="0">
+        <item row="5" column="0">
          <widget class="QCheckBox" name="autoSplitStrings">
           <property name="toolTip">
            <string>Splits a string into two lines by adding an end quote at the cursor position when you press Enter and a start quote to the next line, before the rest of the string.
@@ -150,6 +208,8 @@ In addition, Shift+Enter inserts an escape character at the cursor position and
          </widget>
         </item>
        </layout>
+      </item>
+     </layout>
     </widget>
    </item>
    <item>