Minesweeper

A terminal game of Minesweeper in C# for .NET 10, plus a built-in solver so the game can be played, scripted, and tested without a keyboard.

dotnet run --project src/Minesweeper            # play (Beginner)
dotnet run --project src/Minesweeper -- -d expert
dotnet run --project src/Minesweeper -- --auto  # watch the solver play

Playing

Key	Action
arrow keys, Home, End	move the selector
space / enter	open a square, or chord when standing on a number
c	chord the number under the selector
f (or /)	flag a suspect square
q (or ?)	question mark a square
p	pause (freezes the clock)
n	new game on the same board
d, 1, 2, 3	next difficulty, or jump to Beginner / Intermediate / Expert
s	dump the board as text, then return
h or F1	key list
esc	quit and print the final board

Rules are the classic ones: the first click is never a mine (and by default opens an area), a number with exactly as many flags around it as it needs opens the rest, and flagged squares hold back a flood fill. Losing shows every mine and marks flags that were on safe ground.

Options

--help lists everything. Highlights:

minesweeper -d intermediate            # 16x16 with 40 mines
minesweeper -s 30x20x120               # any board up to 120x60
minesweeper -s 12x8 -m 5               # size plus mine count
minesweeper --seed 42                  # reproducible mines and solver guesses
minesweeper --compact --ascii          # one plain ASCII character per square
minesweeper --no-color                 # monochrome (NO_COLOR is honoured too)
minesweeper --auto-trace --seed 7      # print every solver decision
minesweeper --list-levels              # show the presets

Auto mode

--auto runs the solver in src/Minesweeper/Game/Solver.cs: it applies the two deductions every player uses (a number touching exactly as many hidden squares as it still needs is all mines; a satisfied number chords), then guesses the lowest risk square when logic runs out. It prints the finished board and exits with 0 on a win, 1 on a loss, which makes it a handy end-to-end check:

dotnet run --project src/Minesweeper -- --auto -d beginner --seed 7

Layout

Path	What lives there
src/Minesweeper/Game/Board.cs	grid, mine placement, flood fill, chording
src/Minesweeper/Game/MinesweeperGame.cs	one round: safe first click, flags, win/loss
src/Minesweeper/Game/Solver.cs	the deduction and guessing strategy
src/Minesweeper/Cli/ConsoleRenderer.cs	flicker-free drawing (only changed squares are written)
src/Minesweeper/Cli/InteractiveRunner.cs	keyboard loop, clock, pause, difficulty switching
src/Minesweeper/Cli/Options.cs	command line parsing
tests/Minesweeper.Tests	rules, solver, difficulty and CLI tests

The game logic has no console dependencies, so it can be unit tested or driven headlessly.

Building and testing

dotnet build            # or dotnet run --project src/Minesweeper
dotnet test             # 65 tests

Standalone binaries

./publish.sh produces a self-contained, trimmed, single-file binary for each runtime under artifacts/<runtime>/. Nothing has to be installed on the machine that runs them.

./publish.sh                    # linux-x64 and win-x64
./publish.sh linux-arm64        # any runtime identifier

dotnet publish src/Minesweeper -c Release -r win-x64 --self-contained \
  -p:PublishTrimmed=true -p:PublishSingleFile=true   # the same thing by hand

Binary	Size	Runs on
artifacts/linux-x64/minesweeper	14 MB	64-bit Linux with glibc
artifacts/win-x64/minesweeper.exe	13 MB	64-bit Windows 10 or newer

Trimming keeps only the runtime the game touches, and the publish is warning free. Windows binaries can be cross-compiled from Linux or macOS; --self-contained false gives a small framework-dependent binary instead.

Notes

• Interactive play needs a real terminal. With output redirected the game says so and points at --auto.
• Board squares are two characters wide so the field looks square; the game quietly drops to one character when the terminal is too narrow, and refuses boards that still cannot fit.
• Colors come off automatically when NO_COLOR is set; --ascii swaps the shaded blocks, flags and mines for #, F, * if a terminal struggles with them.
• A board keeps at least one safe square: asking for more mines than fit is an error, and a board too small for the safe zone simply ends up with fewer mines.