Breakpoints
Breakpoints are special markers that suspend program execution at a specific point. This lets you examine the program state and behavior. Breakpoints can be simple (for example, suspending the program on reaching some line of code) or involve more complex logic (checking against additional conditions, writing log messages, and so on).
Once set, a breakpoint remains in your project until you remove it explicitly, except for temporary breakpoints.
Types of breakpoints
The following types of breakpoints are available in RubyMine:
Line breakpoints: suspend the program upon reaching the line of code where the breakpoint was set. This type of breakpoints can be set on any executable line of code.
Exception breakpoints: suspend the program when the specified exception is thrown. They apply globally to the exception condition and do not require a particular source code reference.
Set breakpoints
Set line breakpoints
Click the gutter at the executable line of code where you want to set the breakpoint. Alternatively, place the caret at the line and press Ctrl+F8.
To set a temporary line breakpoint, press Ctrl+Alt+Shift+F8. The breakpoint will be removed from your project right after it is hit.
Set exception breakpoints
Press Ctrl+Shift+F8 or select from the main menu.
In the Breakpoints dialog, press Alt+Insert or click
, and select Ruby Exception Breakpoints or JavaScript Exception Breakpoint.
In the Choose Exception Class dialog, specify the exception class from a library or from your project.
Manage breakpoints
Remove breakpoints
For non-exception breakpoints: click the breakpoint in the gutter.
For all breakpoints: go to Ctrl+Shift+F8 in the main menu, select the breakpoint, and click Remove Delete.
To avoid accidentally removing a breakpoint and losing its parameters, you can choose to remove breakpoints by dragging them to the editor or clicking the middle mouse button. To do this, go to and select Drag to the editor or click with middle mouse button. Clicking a breakpoint will then enable or disable it.
Mute breakpoints
If you don't need to stop at your breakpoints for some time, you can mute them. This allows you to resume normal program operation without leaving the debugger session. After that, you can unmute breakpoints and continue debugging.
Click the Mute Breakpoints button
in the toolbar of the Debug tool window.
Enable/disable breakpoints
When you remove a breakpoint, its internal configuration is lost. To temporarily turn an individual breakpoint off without losing its parameters, you can disable it:
For non-exception breakpoints: right-click it and set the Enabled option as required. You can also toggle them with the middle mouse button if removing breakpoints is not assigned to it.
For all breakpoints: click Run | View Breakpoints Ctrl+Shift+F8 and check/uncheck the breakpoint on the list.
Move/copy breakpoints
To move a breakpoint, drag it to another line.
To copy a breakpoint, hold Ctrl and drag a breakpoint to another line. This creates a breakpoint with the same parameters at the destination.
View all set breakpoints
You can view the list of all breakpoints in the Bookmarks tool window. Breakpoints are automatically added to the dedicated list in the tool window once you place them in your code.
In the main menu, go to or press Alt+2 and expand the Breakpoints list.
Configure breakpoints' properties
Depending on the breakpoint type, you can configure additional properties which allow you to tailor its operation for specific needs. The most used options are available via intentions.
To access breakpoint intentions, place the caret at the line with the breakpoint and press Alt+Enter. Use this option when you need to quickly configure basic breakpoint properties.
To access the full list of properties, right-click the breakpoint and click More or press Ctrl+Shift+F8. Use this option for a bird's eye view of all breakpoints and full control over their configuration.
Intentions reference
Intention | Description |
|---|---|
Remove breakpoint | Removes the breakpoint at the selected line. |
Disable Breakpoint | Disables the breakpoint at the selected line. |
Edit breakpoint | Opens a dialog with the most used breakpoint properties. For more properties, click More or press Ctrl+Shift+F8. |
Breakpoints' properties
Enabled
Clear the checkbox to temporarily disable a breakpoint without removing it from the project. Disabled breakpoints are skipped during stepping.
You can configure RubyMine to enable/disable breakpoints on clicking rather than removing them altogether. To do this, go to and set the Remove breakpoint option to Drag to the editor or click with middle mouse button.
Suspend execution
Specifies whether to pause the program execution when the breakpoint is hit.
Non-suspending breakpoints are useful when you need to log some expression without pausing the program (for example, when you need to know how many times a method was called) or if you need to create a master breakpoint that will enable dependent breakpoints when hit.
Condition
This option is used to specify a condition that is checked each time the breakpoint is hit. A condition is a Ruby Boolean expression evaluating to true or false, for example @user.name == "Example User". If the condition evaluates to true, the selected actions are performed. Otherwise, the breakpoint is ignored.
The result of the expression is taken from the return statement. When there is no return statement, the result is taken from the last line of code.
When evaluating expressions, make sure you are aware of their possible side effects as they may potentially affect the behavior and the result of the program.
Logging options
When a breakpoint is hit, the following can be logged to the console:
"Breakpoint hit" message: a log message like
Breakpoint reached at ocean.Whale.main(Whale.java:5).Stack trace: the stack trace for the current frame. This is useful if you want to check what paths have led to this point without interrupting the program execution.
Evaluate and log: the result of an arbitrary expression.
The result of the expression is taken from the return statement. When there is no return statement, the result is taken from the last line of code which doesn't even have to be an expression: a literal works too. This can be used to produce a custom message or to keep track of some values as the program executes.
When evaluating expressions, make sure you are aware of their possible side effects as they may potentially affect the behavior and the result of the program.
Remove once hit
Specifies whether the breakpoint should be removed from the project after it has been hit once.
Disable until hitting the following breakpoint
When a breakpoint is selected in the Disable until hitting the following breakpoint box, it acts as a trigger for the current breakpoint. This disables the current breakpoint until the specified breakpoint has been hit.
You can also choose whether to disable it again after this has happened or leave it enabled.
This option is useful when you only need to suspend the program under certain conditions or after certain actions. In this case, the trigger breakpoint usually isn't required to stop the program execution and is made non-suspending.
Breakpoint statuses
Breakpoints can have the following statuses:
Status | Description |
|---|---|
Verified | After you have started a debugger session, the debugger checks whether it is technically possible to suspend the program at the breakpoint. If yes, the debugger marks the breakpoint as verified. |
Warning | If it is technically possible to suspend the program at the breakpoint, however there are issues related to it, the debugger gives you a warning. This may happen, for example, when it is impossible to suspend the program at one of the method's implementations. |
Invalid | If it is technically impossible to suspend the program at the breakpoint, the debugger marks it as invalid. The most common cause for this is that there is no executable code on the line. |
Inactive/dependent | A breakpoint is marked as inactive/dependent when it is configured to be disabled until another breakpoint is hit, and this has not happened yet. |
Muted | All breakpoints are temporarily inactive because they have been muted. |
Disabled | This breakpoint is temporarily inactive because it has been disabled. |
Non-suspending | The suspend policy is set for this breakpoint so that it does not suspend the execution when hit. |
Breakpoint icons
Depending on their type and status, breakpoints are marked with the following icons:
Line | Exception | |
|---|---|---|
Regular |
|
|
Disabled |
|
|
Verified |
| |
Muted |
| |
Inactive/dependent |
| |
Muted disabled |
| |
Non-suspending |
| |
Verified non-suspending |
| |
Invalid |
Productivity tips
- Use breakpoints for "printf" debugging
Use non-suspending logging breakpoints (sometimes referred to as watchpoints in other debuggers) instead of inserting print statements in your code. This provides a more flexible and centralized way of handling debug log messages.
- Set logging breakpoints more quickly
To set a non-suspending logging breakpoint, hold Shift and click the gutter. This will not suspend the program execution and instead log a message like
Breakpoint reached. If you want to log some expression that is in front of you in the editor, select it before holding Shift and clicking the gutter.- Add breakpoint descriptions
If you have many breakpoints in your project, you can add descriptions to breakpoints for ease of search. To do this, right-click a breakpoint in the Breakpoints dialog Ctrl+Shift+F8 and select Edit description from the menu. Now when you start typing the breakpoint name, it gets the focus.
- Group breakpoints
You can organize breakpoints into groups, for example, if you need to mark out breakpoints for a specific problem. To do this, in the Breakpoints dialog Ctrl+Shift+F8, select a breakpoint you want to place in a group and select from the menu.
- Jump to source
To jump from the Breakpoints dialog to the line of code where the selected breakpoint is set, press F4.